A Danish shipyard worker has died three days after being caught in an explosion on a dredger.

Grenaa Shipyard told television station TV2 Ostjylland on Sunday that the 31-year-old passed away following a blast on Thursday morning on the 500-dwt Grete Fighter (built 1980).

Employees and management are deeply concerned over the fatal accident, said chairman Esben Moller.

The man had been flown to hospital in Copenhagen with two colleagues on Thursday.

The other injured men were Danish nationals aged 53 and 50. They suffered severe injuries.

Two more staff were treated for smoke inhalation, East Jutland Police said in a tweet.

Moller told TV2: "There are about 30 employees at the yard, and there were many people in the vicinity. People say that it could just as well have been me."

He added he was very surprised that the accident could happen because everyone is very aware of the risk of gas explosions when carrying out welding work.

The vessel is operated by Danish company Peter Madsen Rederi.

Probe begins

East Jutland Police have asked the Labour Inspectorate to assist with its investigation.

A fire on the ship after the explosion has been extinguished.

TV2 cited an eyewitness as saying: "I can see a lot of people turning around and pulling people down from the cargo hold."

The observer, named as Lars Pedersen, said firefighters had masks and oxygen bottles, while four ambulances, five police cars and two medical helicopters arrived at the scene.