The Labor Department (search) and market regulators said Friday they were looking into a possible leak of employment data because of significant moves in financial markets before official release of the report.

While the Labor Department stressed it did not believe a leak had occurred, the Securities and Exchange Commission (search) and Commodity Futures Trading Commission (search) said they were reviewing market activity around the time of release of the closely-watched March payrolls report.

Some analyd the surprisingly robust jobs report was leaked before its official 8:30 a.m. embargo, causing unusually large price movements in financial markets about two minutes before the official release time.

Bond, currency and stock futures markets all showed moves greater than the usual volatility that is often seen ahead of the release of closely watched economic data.

The report said that U.S. non-farm payrolls climbed a steep 308,000 in March -- the biggest gain since April 2000 and well above the 103,000 rise expected by Wall Street.

"I think it's accurate to say we are looking into it and talking to other parties that would have an interest in making sure that something didn't happen that was inappropriate," Alan Sobba, the CFTC's director of external affairs, told Reuters.

SEC spokesman John Nester said: "We're looking into it. The SEC routinely looks at trading that takes place in advance of market-moving news."

A spokesman at the U.S. Labor Department said it was not unusual for markets to move just before data is released as traders place last-minute bets on the numbers.

"We're reviewing our procedures and reviewing today's lockup. We have no indication ... that there was indeed a leak," Labor Department spokesman Bob Zachariasiewicz told Reuters.

Many market players believe the data began to leak into the market a few minutes before the official release time.

"You can see the price action. It smells like a leak and walks like a leak. It happened two minutes before the release ... You could see the euro was selling off against the dollar," said Monica Fan, chief currency strategist for Europe at Royal Bank of Canada.

The large price moves began in the fixed income market, traders said.

"It started in the fixed income market and then spilled over into forex. Not just one or two trades. The whole market was involved," said one senior dealer at a major European bank in New York.

Several groups of people get an early look at the payrolls report. Bureau of Labor Statistics (search) officials have parts of the data for several days before it is released, but security at the agency is tight.

On the day before the release, the number is given to President Bush through his economic team, the Council of Economic Advisors. The BLS said it gives the data to no one else. Neither the Labor Secretary, Elaine Chao, or Federal Reserve Chairman, Alan Greenspan, see the data ahead of its release, though it is widely believed Bush's advisors share the data with key cabinet and Fed officials so they can prepare a response.

Finally, 30 minutes before the 8:30 a.m. embargo, journalists are given the data in a locked room at the Labor Department. Communication is restricted and journalists agree not to transmit the data early.

Some market players at first suggested Treasury Secretary John Snow had indicated the number was going to be surprisingly strong, after he said Thursday: "I think we'll see that we are beginning to create a lot of new jobs."

But Snow also explicitly said he had not seen the report, and a Treasury spokesman said Snow was simply repeating his oft-stated belief that the jobs market was looking up, rather than focusing specifically on March data.

Reuters Group Plc, the news and information provider, was also briefly a suspect after one of its stories was sent to some clients with an 8:28 a.m. timestamp. But company officials explained that a technical glitch had produced the incorrect timestamp and stressed that it did not break the data embargo.