A senior U.S. counterterror official says a passenger aboard a Delta Air Lines flight in Detroit was planning to blow up the plane but the explosive device failed.

The official said the passenger was being questioned Friday evening. It was not immediately clear why the passenger wanted to attack the flight that was arriving from Amsterdam.
The official spoke on condition of anonymity because the investigation was continuing.
Authorities initially believed the passenger had set off firecrackers that caused some minor injuries.
A Delta spokeswoman said the passenger was immediately subdued.
She had no details on the injuries.
A White House official in Kailua said the airline incident was attempted act of terrorism.