NEW YORK -- Tests of chemicals removed from the offices of United Nations came back negative for the deadly nerve gas phosgene, two law enforcement sources told WNBC.com.

The tests were done at a U.S. military lab over the weekend and apparently show the chemicals are not lethal as first feared.

Officials did not say what lab officials now believe the specific chemical breakdown of the substance is. They said more testing still needs to be done.

A U.N. spokesman said the agency is still awaiting final test results, but added that it appears there was no danger at any time. The spokesman said an internal review of the incident will soon be underway.

The potentially dangerous chemicals were found in vials in a U.N. office building on Thursday. FBI, NYPD and FDNY hazardous materials units responded to remove them.

U.N. officials initially said the vials were found at 866 E. 48th St. and possibly included one vial of phosgene, a chemical warfare agent.

Officials said the vials were recovered from a former Iraqi chemical weapons facility by U.N. weapons inspectors back in 1996.

Sen. Charles Schumer, D-N.Y., said the incident should serve as a warning.

"The U.N. should know it's a target," Schumer said in a statement. "They need to be even more careful than anyone else. The fact that a container of deadly poison from Iraq was found at the U.N. is a wakeup call that they better start living up to the higher safety standards of a post-9/11 New York."

It is unclear why the materials were at United Nations offices on the East Side. A U.N. spokeswoman said the materials were normally sent directly to a lab for testing.

An FBI spokesman in New York said, "There is no hazard to the people of New York from this operation."

Officials said the items were sealed in plastic bags and a metal box.

Homeland Security in Washington said the two small packages were found in the offices of the U.N. Monitoring, Verification and Inspection Commission during a routine archives check.

DHS spokesman Russ Knocke said the items were shipped more than 10 years ago and that "there is no indication of questionable activity."

Officials said the materials would be removed safely and transported to a laboratory for further analysis.