According to the Associated Press, the explosion was the result of a malfunctioning piece of construction equipment in the headquarters' lobby.
From the AP:
Emergency responders were dispatched to the police division Tuesday evening after employees on multiple floors of the building heard an explosion. Police say the boom was traced to a battery in a hydraulic ladder in the lobby that was being used for an insulation project.
No one was injured, and there was no major damage. Bomb squad members and federal investigators were sent to the scene as a precaution.
Original story below.
Investigators are looking into reports of an explosion at Columbus Police headquarters in downtown Columbus, Ohio. Homeland Security Officials were on the scene at around 8:30 p.m. ET on Tuesday, WBNS-TV reports.
"A loud noise was heard inside the building in the 100 block of Marconi Boulevard around 7:30 p.m. Tuesday," the report states. "The Franklin County Jail, located on South Front Street, was placed on lockdown at about 9:30 p.m."
The building was evacuated as police and fire crews searched for the source of the possible explosion. There were no reports of injuries.
An officer inside the building told WBNS-TV that he smelled gun powder at the time of the reported explosion.
Reports of "suspicious people" also surfaced at around the same time. There were K9 units seen searching nearby parking garages for explosives late Tuesday as police closed some streets near the police headquarters.
This is a breaking news story and will be updated.