Pilots of American Airlines flight 199 were forced to make an emergency landing after the windshield shattered.
The JFK-bound plane landed at Heathrow Airport, where a cabin crew member captured the extent of the damage to the Boeing 767-300 and uploaded a photograph to Twitter.
A spokesperson for the airline confirmed that a maintenance issue caused the diversion after take-off from Milan but say the aircraft is being investigated to determine the cause.
The Boeing 767-300 departed from Milan-Malpensa Airport and was scheduled to arrive in John F. Kennedy International Airport.
The plane instead landed shortly after take-off at Heathrow.