Dogs smell explosives; office evacuated

James A. Rhodes State Office Tower

COLUMBUS, Ohio (CNN) -- Authorities evacuated a 41-story state office building Wednesday after a suspicious man told a worker he was "here to install a bomb," officials said.

A worker on the 28th floor of the James A. Rhodes State Office Tower in downtown Columbus confronted the man who appeared to be out of place, said Ohio State Highway Patrol spokesman Lt. Col. Paul McClellan.

"He was an unusual person on the floor. She knew he did not belong there," McClellan said.

When she asked what the man was doing, McClellan said he replied, "I'm here to install a bomb." State troopers apprehended the man and found his vehicle at the building's loading dock.

Authorities ordered the evacuation after a bomb-sniffing dog alerted to the smell of explosives in the vehicle three times.

Another dog, belonging to the federal Bureau of Alcohol, Tobacco and Firearms, also alerted to the presence of explosives, McClellan said.

McClellan said no explosives were found.

Lt. Gov. Maureen O'Connor, who is in charge of the Ohio Security Task Force, said the man was a Mexican national employed by a window treatment company that was doing some work in the building.

She said she believes he is an illegal immigrant and as far as she could determine did not have a criminal record.

McClellan said authorities conducted a thorough sweep of the 28th through 30th floors of the building.

The suspect was in custody but had not been charged, McClellan said.

About 4,000 state employees work at the building, which houses the Ohio Supreme Court and other government offices. The building is across the street from the Ohio Statehouse, or capitol building. Born said the Statehouse was not evacuated.

CNN Homeland Security Correspondent Jeanne Meserve contributed to this report.