A Delta Air Lines flight made an emergency landing Wednesday after a passenger attempted to gain entry to the cockpit. The Boeing 747, Delta Flight 2557, en route to Atlanta had just taken off from Hobby Airport in Houston.

“We had a passenger get up and try to access the cockpit,” the pilot radioed to air traffic control. “Can you coordinate and have security standing by?”

The unruly passenger was restrained and the cockpit was secured. Upon confirming that with air traffic control, the pilot also requested emergency medical personnel to be on hand.

“(He is) in cuffs in the back of the aircraft, but he did assault another passenger, so we would like that other passenger checked out,” the pilot said.

The pilot used the emergency transponder to signal an emergency and landed back at Hobby Airport just 17 minutes after takeoff. Emergency vehicles accompanied the aircraft to the gate.

An air traffic controller told emergency responders, “They are coming to the gate. The police are there waiting. Follow the aircraft to the ramp.”

The airplane took off again and arrived in Atlanta 90 minutes after its scheduled arrival time.

Later, Delta told CNN, in a statement that appeared to contradict the pilot’s account, that the passenger “approached crew and customers but did not make contact with or attempt to access the flight deck.”

It remains unclear whether the passenger attempted to enter the cockpit.

The airline issued a statement saying, “The safety of our customers and crew is paramount, and Delta has zero tolerance for unruly behavior. We apologize to our customers for this experience and delay in their travels.”