A cab driver in Philadelphia claims he may have picked up two convicted murderers who escaped from prison this weekend.

The cab driver told police that he picked up two men this morning who fit the description of David Sweat and Richard Matt, who recently escaped from the Clinton Correctional Facility in New York.

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WTXF reporter Jennifer Joyce reported this morning on “Fox and Friends” that the cab driver said he picked up the two men in Center City at around 4:15 a.m. and dropped them off at the 30th Street station, where Amtrak is located. He did not report this to police until after he took a job at the Philadelphia International Airport.

The cab driver is now reviewing surveillance video from the station with police, Joyce said.

Police say this is an extremely preliminary possible sighting.

Stay tuned to Fox News throughout the day for updates on the manhunt.

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UPDATE: David Lee Miller reported from several miles outside the prison on "America's Newsroom."

Miller said police have sealed off a perimeter around the prison, believing it's possible that Matt and Sweat are in the vicinity.

Miller said there was a lot of activity in the area Tuesday, especially late at night. Schools have been closed and people instructed to stay indoors. 

It's believed that sniffer dogs picked up the scent of the two inmates in the area. Miller said there have been over 500 leads and all will be followed up on. 

He said there has been no confirmation on the accuracy of the possible sighting in Philadelphia.

Watch the report below.