Four Floors of City Hall Evacuated : Bomb scare: A box containing ‘suspicious chemicals’ and addressed to the mayor is discovered by a mail room worker.

Four floors of City Hall were evacuated Wednesday while the Los Angeles Police Department’s bomb squad removed a box full of “suspicious chemicals” that had been mailed to Mayor Tom Bradley.

The package was discovered at 11:30 a.m. by a staffer in the mezzanine mail room who noticed it was dripping toxic mercury, a Los Angeles Police Department spokesman said.

“Bomb squad experts X-rayed the device at the scene and what they saw in there was enough for them to treat it as a potentially dangerous device,” LAPD Lt. John Dunkin said. “There were vial-shaped objects and wiring inside.”

Mercury is sometimes used in motion switches for car alarms, as well as explosive devices, authorities said.

Los Angeles firefighters cordoned off a stairwell outside the mayor’s office leading up to the mail room and evacuated about 300 people from the first, second and third floors, as well as the fourth floor mezzanine directly above Bradley’s office.

Bradley was not affected by the evacuation because he was in Sacramento most of the day, holding discussions with Assembly Speaker Willie Brown on the impact that state budget cuts might have on cities.

“Obviously, I was concerned about the safety of the people in this building,” Bradley told reporters upon his return to Los Angeles. “Unfortunately, there are people in our society who mail explosive devices or hazardous devices.”

The two-hour evacuation closed the offices of the mayor, several City Council members and the city clerk--all but paralyzing city business.

Rescue ambulances were parked nearby as firefighters closed Spring and Main streets between 1st and Temple streets while the package was removed from City Hall and loaded into a special “bomb bucket” for transport to the Sepulveda Basin in the San Fernando Valley, LAPD Detective Thomas King said.

It was inspected by explosives experts there, who determined that it was filled with “suspicious chemicals,” LAPD Cmdr. Bayan Lewis said. He said there were no wires inside the parcel after all.

“The package was taken apart and it was determined that it did contain vials of mercury and some other liquid,” Lewis said. “Exactly what is in those vials has not been determined yet.”

The city employee who discovered the brown package described it as being about two feet long and six inches wide, and dripping globules of mercury.

The staffer said she was trying to scoop up the material with her bare hands when a co-worker warned her away and called police.

The incident is being investigated by the County Department of Health Services and U.S. postal inspectors. Authorities said the package included a return address, but declined to discuss the investigation.