An armed man sparked a two-hour police siege as he impersonated the Incredible Hulk and "barked like a dog" at frightened bystanders.

Witnesses at Brighton Marina told how the man, thought to be in his 30s and half-naked, angrily flexed his muscles - just like bodybuilder Lou Ferringo who played the character in the cult Seventies series - and barricaded himself onto a boat.

Officers defended themselves with riot shields and tried to talk him down as he doused them with a flammable liquid and hurled a claw hammer, shards of glass and other projectiles.

Bystander Martin Wheeler said: "He was very red and really pumped up. He was flexing all of his muscles like the Hulk."

The man had first been spotted in the boatyard shortly after 11am.

Pete Jones, who had been working on a boat, said: "A couple of guys heard noises coming from one of the yachts so they knocked on the hull.

"All of a sudden this guy came bursting out of the hatch and starting growling like a dog."

The workers spotted a weapon in his hand and fled in fear. The man, wearing only a pair of shorts, jumped from the boat on to another and then down to the ground below.

He then barricaded himself into a barge called Aussie.

Marina security staff were called, followed by the police. Initial attempts to negotiate with the man failed, as he continued to rip apart the interior of the boat.

More than a dozen officers were involved in the siege that followed. A scaffold was used to raise officers to the level of the boat's windows.

Shocked bystanders said the man tried to stab himself with a screw driver.

Police initially thought he had wounded his neck but he was later found to have a hand injury.

A fire engine waited on standby in the boatyard in case the man tried to ignite any flammable liquid.

Police officers wearing stab vests and carrying shields stormed the vessel at 1.20pm and subdued the man with pepper spray, pinning him to the floor, handcuffing him and carrying him into a police van strapped to a stretcher.

He was checked by paramedics before being arrested for affray and taken into custody.

Mr Jones said: "I don't know whether he had taken something but he was completely out of it, He was foaming at the mouth and kept screaming and roaring. He never said any words though, it was just a screaming noise."

No police officers were hurt in the arrest.

Cynthia Howe, who had been working on her boat in a tent next to the Aussie, said: "It was very shocking. I've never seen anything like it here before."

The man, who was not known to the staff and managers in the boatyard caused hundreds of pounds of damage to the boat. Its owner, who did not know the man, was called by the management after the incident started.