Both the Federal Aviation Administration and the National Transportation Safety Board said Monday that they are investigating the incident in which a Republic Airways jet had to abort takeoff and slam to a stop because a United Airlines plane was still taxiing across the runway. The close call happened despite the airport being equipped with an advanced surface radar system that’s designed to help prevent such close calls.

In audio from the tower that ABC obtained from the website www.LiveATC.net, the air traffic controller said to the pilot of the Republic Airways jet: “Sorry, I thought United had cleared well before that.”

At the time that the controller was directing the Republic Airways jet to take off, a ground controller on a different radio frequency was directing the United plane to a new taxiway after it missed the first one it was supposed to use to exit the runway.

When the passengers got off the plane after the close call at 12:35 a.m., Hoffer said the gate agents refused to even give them hotel vouchers for the night because they blamed the weather,r even though another passenger said she had an app on her phone that showed another plane was on the runway.