NEWARK, N.J. (AP) — Three people running late for a flight triggered a security alert in Terminal C at Newark Liberty International Airport.

The Transportation Security Administration says a man, woman and teenage boy set off an alarm when they tried to open a jet bridge door just after 3 p.m. Monday.

The trio missed their flight to Nashville.

However, TSA spokeswoman Ann Davis told The Star-Ledger of Newark confusion over whether they were on the plane prompted Continental Airlines to bring the flight back. The plane departed 36 minutes late.

Three checkpoints in the terminal were closed for 10 minutes, causing a backlog of passengers.

The incident came just days after a mail bomb plot was thwarted on Friday. Two packages from a UPS cargo plane at Newark were checked.

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