Officials were venting the tunnel, but heavy delays were reported.
Construction workers excavating the site of a former diner struck a gas main in Jersey City, briefly forcing the closure.
The worker was digging a large hole when he struck a 1-inch main at the 14th Street site just before 10 a.m. PSE&G workers quickly responded and shut off the gas line.
New Jersey-bound lanes of the Holland Tunnel were temporarily closed while the main was capped.
The construction site was the former home of the Tunnel Diner, a landmark eatery that appeared in the 1996 film "City Hall." It closed in 2007 and was demolished after failing to attract a buyer.
The Holland Tunnel reopened around 10:30 a.m.
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