By Brad Segall

NORRISTOWN, Pa. (CBS) –- Montgomery County prosecutors say a criminal investigation is now underway after threats forced the shutdown of the courthouse in Norristown for a couple of hours this morning.

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District attorney Risa Ferman says they are following significant leads after a pair of calls came into Norristown police and the county’s emergency operations center, shortly after 8:30 a.m.  The callers said there were explosives and bombs inside the courthouse.

That triggered an immediate evacuation and a top-to-bottom search that included 100 sheriff’s deputies and nearly a dozen bomb-sniffing dogs.

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“We shut down court, we stopped the swearing-in ceremony for the commissioner,” notes Ferman.  “People who were coming to this building for business they had were seriously inconvenienced,” she said, adding that charges could be filed.

At this point, authorities don’t have any information that this incident is related in any way to another bomb threat that forced an after-hours search of the courthouse last month.

Around 11 a.m. the scene was cleared and everyone was allowed inside.

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