A flight from Washington DC to Houston was canceled today, due to a specific threat: Airline Cancels Washington-Houston Flight.

Department spokesman Brian Roehrkasse said Flight 1519 was canceled “due to security concerns and threat reporting about that particular flight.”

He added that the federal agency and Continental “worked closely on the matter,” but did not give any further details of the threat.

The cancellation came on the heels of announcements Saturday that six international flights scheduled for Sunday and Monday were canceled because of security concerns.

In Houston, Continental spokesman David Messing said the Sunday domestic flight was canceled “because we were unable to get security clearance from the Department of Homeland Security.”

Messing said he did not know what security concerns the agency had and that passengers were being booked on other flights.

The flight was scheduled to take off from Dulles International Airport outside Washington at 5:45 p.m. EST and arrive at Bush Intercontinental Airport at 8:10 p.m. CST.

The National Football League’s Super Bowl was being played Sunday evening at Reliant Stadium, approximately 27 miles from the airport.

However, a U.S. government official said the flight cancellation was not specifically connected to the Super Bowl.