[UPDATE- Access Restored - SEE BELOW] Penn Station was shut down to incoming and outgoing passengers at the height of the pre-Thanksgiving Wednesday night rush hour. The closure came after the station became too crowded when signal problems cut off train service for the LIRR and NJ Transit (and eventually Amtrak). As if the crowds at Penn Station weren't bad enough this afternoon!

No further passengers are being allowed into Penn. NJ Transit says its trains are delayed indefinitely and Amtrak is also reporting delays.

The problems began with the signal problems around 5:30 p.m. according to an MTA spokesman. It is unclear when the situation at Penn will be back to normal. In the meantime those at or trying to get to Penn are advised to go to Atlantic Terminal or Jamaica Station for service. LIRR tickets are being cross honored at Penn and Jamaica, according to the city's Office of Emergency Management.

Update 7:00 p.m.: After one of the worst timed transit breakdowns possible, access to Penn has been restored with eastbound service slowly coming back. Expect SERIOUS delays!

Update 7:40 p.m. And westbound LIRR service has now also been restored. But seriously, expect massive delays tonight.