The emergency services have been at the scene at the Lisahally terminal
Three men have fallen from a crane on the outskirts of Londonderry.
It happened at about 09:45 BST on the Port Road near Lisahally port.
It is believed the men fell more than 15ft (4.5 metres) from the cradle of a crane onto a boat.
The Northern Ireland Ambulance Service said the three men have been taken to Altnagelvin hospital. One has back and neck injuries, a second has back injuries and the third has been described as "walking wounded".
The port and the harbour are to launch an investigation into what happened.
The Health and Safety Executive said it will also investigate.
