Financial workers in New York, seven months after the attack that destroyed the World Trade Center and killed about 3,000 people, appeared largely to take in stride Friday an FBI alert about possible attacks against Northeast banks.

Learning the FBI had "unsubstantiated information" that "unspecified terrorists" were considering attacks against U.S. financial institutions, Christopher Low, chief economist at FTN Financial in New York, said people in the industry were talking about the potential danger but did not seem worried.

"I'd be surprised that anybody in the market took it too seriously," Low said.

U.S. stock prices dipped briefly after word of the report, but soon recovered.

In Washington, a U.S. official said the threats were believed to be coming from the al Qaeda network of Osama bin Laden, blamed for the Sept. 11 attacks on the United States.

The alert said the information received showed the attacks would be in the Northeast, particularly on banks, covering Virginia, Maryland, Delaware, Pennsylvania, New York, New Jersey, Connecticut, Massachusetts, Rhode Island, Maine, Vermont, New Hampshire and the capital, Washington.

The FBI said the alert did not change the level of threat in the country, which remains at an elevated level of risk.

New York Police Commissioner Ray Kelly said at an afternoon news conference the city's police force was alerted of the FBI warning and was told to be extra vigilant at banks and other financial institutions.

"What we've done is put our personnel on a higher state of awareness," Kelly said. Since the Sept. 11 attack on the World Trade Center that dealt a blow to the city's financial center, New York has been on its highest level of alert.

FleetBoston Financial Corp. , the No. 7 U.S. bank holding company, said it took immediate steps to tighten security after the FBI's warning.

"But we're not discussing what those steps are," said Jim Mahoney, a FleetBoston spokesman. He added no threats had been made against the bank.

He said the Boston-based bank was in close contact with Massachusetts and federal law enforcement. There were no plans by the bank to curtail operations, Mahoney said.