Insider trading "appears to be rampant" among Wall Street securities professionals, she added.

Alice Fisher, assistant attorney general with the Justice Department's criminal division, echoed Thomsen's sentiment and said: "The number of insider trading cases don't seem to be going away."

In the past year, SEC enforcement lawyers have brought increasing numbers of insider trading lawsuits and settlements. Recent high-profile cases include charges against a husband and wife in Hong Kong for trades in Dow Jones & Co Inc shares ahead of News Corp's $5 billion takeover bid, and guilty pleas from three former Countrywide Financial Corp executives for trading company shares ahead of a disappointing profit report.

Also, in March U.S. prosecutors charged 13 people, including employees at top Wall Street banks UBS, Morgan Stanley  and Bear Stearns Cos Inc in what they called one of the most pervasive trading rings since the 1980s. The SEC also brought civil charges against 11 people, as well as against three hedge funds.

Insider trading involving hedge funds is the focus of one of the four internal working groups the SEC has set up to tap expertise and coordinate efforts throughout the agency. The $1.8 trillion hedge fund industry guards its secrecy and complex trading strategies.

Abreu was the director of records at the medical examiner's office. Her co-defendant and former boss, Natarajan Venkataran, was scheduled to go to trial on Nov. 26. Abreu was Venkataran's assistant.

Abreu was responsible for supporting computer systems used to track and identify forensic evidence, including DNA, from crime scenes, prosecutors said. After the Sept. 11 attack, the office needed more computer services to identify victims through evidence collected at ground zero.

The two, charged in 2005, steered more than $13 million in computer service contracts and purchase orders between 1999 and 2004 in exchange for cash payments to companies that did little or no work, according to U.S. Attorney Michael Garcia.

The two also directed millions of dollars to three shell companies they created, withdrew cash and made payments to personal accounts and transferred money overseas, prosecutors said.

Many of the office's Sept. 11-related expenses were reimbursed by the Federal Emergency Management Agency, which forwarded more than $46 million to the office in 2002 and 2003, federal authorities said.

"We stay his execution pending the Supreme Court's resolution of Baze vs Rees," the court said, referring to the high court's decision last month to review whether lethal injections cause unacceptable pain.

Siebert's lawyers had argued that the drug combination used for lethal injection might interact with his medication for pancreatic cancer and hepatitis C and cause undue pain.

Siebert was convicted of the 1986 strangling deaths of Sherri Weathers, her two young sons and Weathers' friend Linda Jarman. Also convicted of murdering another woman, Siebert claims to have murdered others in various U.S. states.

Bryan Stevenson, director of the Equal Justice Initiative, which helped bring the suit on Siebert's behalf, said: "It would grossly inappropriate to carry out executions that may soon be declared unconstitutional by the Supreme Court."

Louella Kelley, Jarman's sister, lamented the ruling. "He's beaten the system again," she said in an interview. "He got himself educated in law while he's been in prison and his lawyers are very, very good. But all along he's been smarter than our justice system."

Alabama Gov. Bob Riley had said on Monday the execution would go ahead. It would have been the first since the beginning of a "creeping moratorium" that has halted executions in at least six U.S. states. 

In a 6-3 split decision, the court refused to grant Ryan or co-defendant Larry Warner the so-called "en banc" hearing.

Ryan, a Republican who gained national prominence as governor for his opposition to the death penalty, was sentenced to 6 1/2 years in federal prison after his conviction. But the sentence had been put on hold and he remained free while the request for another hearing was pending.

It was not clear from Thursday's ruling whether Ryan would now be required to report to prison. Ryan did not return a message left on his cell phone, and the office of his attorney James R. Thompson said it had had no immediate comment. Thompson, himself a former governor, had said earlier that the case would be fought to the U.S. Supreme Court if necessary.

Ryan was convicted of taking payoffs from political insiders in exchange for state business while he was secretary of state from 1991 to 1999 and governor from 1999 to 2003.

In 2000, Ryan declared a moratorium on executions after 13 Illinois death row inmates were found to have been wrongly convicted. Then, days before he left office, he emptied out the state's death row, commuting the sentences of all 167 inmates to life in prison.

But the federal investigation of the secretary of state's office under Ryan eventually ensnared him. It had been speeded up after six children died in 1994 in a fiery accident involving a truck driver who got his license illegally.

Authorities eventually found that unqualified truck drivers had obtained licenses through bribes. Federal prosecutors began convicting his employees and friends, moving closer and closer to Ryan.

Thursday's order from the six majority judges was just one paragraph long and gave no explanation for their refusal to hold a hearing.

Ryan's request for a new trial cited problems that had surfaced during the jury's lengthy deliberations, including the dismissal of a juror who had allegedly snored and another who failed to disclose her arrest record. His lawyers argued that the questioning of jury panel members about the problems had intimidated them and affected their impartiality. Prosecutors scoffed at the notion.

Oscar Allen, of Williamsburg, Va., waived indictment and pleaded guilty in U.S. District Court for the Eastern District of Virginia to a criminal information charging him with conspiracy to travel in interstate commerce to aid in illegal gambling and to sponsor a dog in animal fighting.

According to court documents, in or about 2001, Allen -- known as "Virginia O" -- bred a litter of puppies for Bad Newz Kennels, the name of Vick's dogfighting operation, for use in animal fighting. One of the puppies was a male pitbull named Magic. In or about 2002 or 2003, Allen also sold Vick and his co-defendants a female pitbull named Jane, according to the documents. Both dogs are mentioned by name in court documents in Vick's case.

Allen also acknowledges that he gave members of Bad Newz Kennels, comprised of Vick, Purnell Peace, Quanis Phillips and Tony Taylor, advice on the operation of a dogfighting kennel and attended dogfights at Vick's rural Virginia home, 1915 Moonlight Road, in Surry County. Allen also stated that he was present in April 2007 when Vick, Peace and Phillips tested dogs to determine if they would be good fighters. The dogs that did not test well were executed, but Allen said he was not present.

Court documents specifically refer to Bad Newz Kennels and Vick's address, but refer to the co-defendants as M.V., P.P., Q.P. and T.T.

Allen, 67, will be sentenced Jan. 25, 2008, in Richmond in front of Judge Henry E. Hudson, who will also sentence Vick and his co-defendants. He faces a maximum sentence of five years in prison and a $250,000 fine. He was released with conditions.

Vick and his co-defendants also face state charges in Virginia. Another hearing in that case is scheduled for Nov. 27.

In the federal case, Phillips and Peace will be sentenced Nov. 30. Vick will be sentenced on Dec. 10, the same day the Falcons play New Orleans on "Monday Night Football" without the quarterback who has been suspended indefinitely by the NFL. Taylor, the first of the co-defendants to reach a plea agreement, will be sentenced Dec. 14.

Unlike two other security companies operating in Afghanistan and Iraq, Blackwater has said it designates its workers contractors, not employees, because it is a "model that works" and because its guards prefer the "flexibility" of the contractor relationship.

The arrangement has, according to Mr Waxman, wrongly allowed Blackwater to avoid paying social security and Medicare taxes, as well as federal income and unemployment tax - or $32m (£16m) in taxes from May 2006 to March 2007.

The IRS ruling was issued after a single security guard approached the tax authority after a dispute over back pay and other compensation. Although the ruling, which is based on Blackwater exercising control over its worker, applied only to the individual, the IRS alerted Blackwater that it could apply to others.

Blackwater, which has classified 604 security guards as contractors, agreed a settlement with the employee after the ruling. That included a confidentiality agreement that prohibited the employee from contacting "any politician" or "public official" about its details.

"It is deplorable that a company that depends on federal tax dollars for 90 per cent of its business would even contemplate forbidding an employee to report corporate wrongdoing to Congress," Mr Waxman said in a letter to Erik Prince, Blackwater chairman and CEO.

He further alleged that the confidentiality agreement was "particularly suspect" because it was signed by Blackwater general counsel Andrew Howell just as Mr Waxman's committee was stepping up its investigation into Blackwater's activities.

Blackwater said that Mr Waxman's assertions were "incorrect" and took issue with his use of the IRS decision, against which the company has appealed.

The company said the IRS had not made a final determination on the employee and the Small Business Administration had decided Blackwater security contractors were not employees.

Gary Medrano, of Woodbridge, Va., filed the lawsuit on Monday in U.S. District Court for the Southern District of Illinois, saying his 2000 Ford F-150 XLT caught fire in October 2006 because of problems with the cruise control switch. The suit seeks class-action certification.

The 10-count complaint does not seek a specific amount of damages, but is asking for both compensatory and punitive damages.

The Dearborn, Mich.-based automaker has recalled more than 10 million vehicles since 1999 because of engine fires linked to the cruise control systems in trucks, sport utility vehicles and vans.

Ford spokeswoman Kristen Kinley said the company was reviewing the lawsuit, but could not comment on the case. A message seeking comment was left Friday with St. Louis attorney Jeffrey J. Lowe, who is representing Medrano.

Medrano said the fire in his pickup truck was extinguished by the fire department, but the vehicle and its contents were left completely unsalvageable.

The lawsuit said the National Highway Traffic Safety Administration has reported at least 218 similar fires from the cruise control deactivation switches. By June 2005, NHTSA had confirmed at least 65 fires were caused by the failure of the switch system.