PHILADELPHIA (WPVI) -- The ATF now says there was no suspicious device at the federal courthouse in Philadelphia on Monday morning.
Chopper 6 was over the scene in Center City as police investigated the threat around 10 am.
Sources say an anonymous caller reported a bomb was going to detonate, leading officials to evacuate the building.
They also shut down Market Street between 6th and 7th streets.
The all-clear was given soon after.
The incident is still under investigation.
ATF: No suspicious device at federal courthouse in Center City Philadelphia