The family of a man found dead on the back of a killer whale are suing the Florida theme park where the fatality happened.

The law suit contends that the park, Sea World in Orlando, failed to put up signs warning that it was dangerous to enter the whale pool.

The manner of Daniel Dukes' death in July this year is a mystery. No one knows how his naked body ended up draped over the back of Tilikum, the killer whale.

Sea World intends to fight the case

It is not known if the 27 year-old drifter climbed into the pool deliberately or if he fell, or whether Tilikum pulled him in.

The post mortem revealed that Mr Dukes suffered instant hypothermia the moment he hit the water and subsequently drowned.

But his parents are not prepared to accept the possibility that it was suicide, or simply a tragic accident.

Multi-million dollar claim

According to a law suit filed with the Central Florida court, Patricia and Michael Dukes from South Carolina are suing the theme park for several million dollars for pain, suffering and the loss of their only son.

One of the arguments lodged by the family lawyer is that Sea World failed to put up notices warning that the killer whale could kill people who entered his pool.

They also claimed that bruises and puncture wounds are consistent with him having been dragged into the water by Tilikum.

The park is promising to fight the case vigorously. A spokesman for Sea World said that, not only was it incredibly bad judgement to try to take a dip with the killer whale, but the water was ice cold.