WASHINGTON, D.C. (WDCW) – The Federal Aviation Administration is looking into a dangerously close call between two planes on the runway. A Southwest flight that was taxiing and a JetBlue flight preparing to take off almost collided.

Both planes came to a stop before maneuvering away. It happened around 7:40 on Thursday morning. The JetBlue 1554 was on its way to Boston. It was delayed for nearly six hours. The airline said it inspected the plane before it eventually took off.

This comes after efforts by some members of Congress to add flights to Reagan National, but it’s been opposed by many politicians.

In a joint statement, Senators Tim Kaine and Mark Warner said, “DCA’s overburdened runway is already the busiest in the country — and we fear that adding more flights could put passenger safety at serious jeopardy.”

Both airlines said they are cooperating with the federal investigation. Initially, the FAA said that an air traffic controller told the Southwest plane to cross a runway while the JetBlue flight was starting its takeoff roll.