MERCER — The Mercer County Courthouse has been closed indefinitely due to a bomb threat.

Mercer County spokesman Jeffrey Greenburg announced the closure just before 10 a.m. but did not immediately provide other details or answer a call to his cell phone.

Greenburg did not say whether the threat was received by phone, e-mail or other means. And it was not immediately clear how long the courthouse would be closed.

The Blair County courthouse in Hollidaysburg received a similar threat by e-mail on Friday. That was determined to be a hoax.

That courthouse is about 85 miles east of Pittsburgh.