The MTA says a giant drill bit being used in a construction project pierced the ceiling of a subway tunnel in Queens, coming into contact with an occupied train a short distance away from a station platform.
The MTA says the drill hit an F train around 11:45 a.m. Thursday, about 700 feet from the 21st Street station in Long Island City. About 800 passengers were on the train.
The conductor noticed the impact and stopped the train, the authority says. While investigating, workers found debris under the third car and damage to the top of the train and one of its windows.
The 10-inch-wide drill bit did not enter the train and no one was hurt.
Surveillance video obtained by NBC 4 New York shows a crane above ground moving the drill bit into place, then grinding the drill bit downward.
The drill bit somehow pierced the tunnel and continued downward, coming into contact with the outside of the train.
Krissen Simksada, who runs a gas station across the street, said he heard the drilling suddenly stop, "like when you're drilling and you hit a stone."
Work crews began scrambling, and people were "running all over," said Simksada.
Andrew Bookman, who sells books on a sidewalk stand just above the subway station, said he saw hundreds of passengers exiting streetside after a second train was brought in to help transport them from the affected train.
"Can you imagine if that thing hit the train right in the middle?" he said. "It could have been a catastrophe. Thank God it wasn't."
Authorities say the bit was being used in the MTA's $10 billion East Side Access project, which will install an 8-track LIRR terminal at Grand Central Terminal by 2021.
A call to the contractor operating the drill was not returned.
The MTA says it is investigating.