Authorities have confirmed security cameras recorded a bar fight which left an Australian man dead in Thailand.

Benjamin Robb, from Newport in Victoria, had only been in Pattaya, 150km southeast of Bangkok, for 12 hours when he became involved in a drunken brawl at the Ruby Bar last Friday.

Thai paramedics and police were quickly on the scene and Mr Robb was taken to the nearby Pattaya Memorial Hospital, but despite treatment he died in the early hours of Saturday from his injuries, including internal bleeding.

US man Jose Manuel Polanco Junior is accused of attacking the Australian man. (9NEWS)

Benjamin Robb was attacked in a bar in Pattaya.

The fatal fight was between Mr Robb and a 43-year-old American man, identified as Jose Manuel Polanco Junior, who has since been charged with manslaughter.

Police this afternoon confirmed the incident was recorded on a security camera, but are yet to make the vision public.

The CCTV will form part of investigations.

Fresh details of what led to the brawl came to light today, with authorities saying Mr Robb put his hands around the neck of a female bartender.

American man Jose Manuel Polanco Junior, right, speaks with police following the alleged bashing of a Melbourne man. (9NEWS)

Mr Polanco's passport. (9NEWS)

“He grabbed her throat and was squeezing it,” police said.

It's believed that's when Mr Polanco stepped in, allegedly beating Mr Robb until he was knocked unconscious.

Some witnesses claim the 43-year-old stomped on the Australian’s face up to 15 times.

Thai authorities claim Mr Polanco initially fled the scene but later turned himself over to police.

Court documents from the US state of Florida revealed Mr Polanco was previously charged with second degree murder after the death of an 18-year-old student.

Mr Polanco confessed to killing the victim, Michael Cooper, after being paid $20 to look at a problem with his car.

"After questioning the defendant for an hour and ten minutes, the defendant confessed to the murder," the document said.

"He also told the detectives where he disposed of the murder weapon, which was not recovered, and where he disposed of his own bloody clothing, which was recovered."

Mr Polanco's charges were later downgraded and he spent two years behind bars for manslaughter with a firearm.

The US State Department told 9NEWS in a statement they are working with Thai officials.

"We are aware of reports regarding the arrest of a U.S. citizen in Thailand," the statement said.

"When a U.S. citizen is detained overseas, the Department works to provide all appropriate consular assistance.

"Due to privacy considerations, we have no further comment."

Meanwhile, The Ruby Club, in a statement, said the altercation had been brief and had left the Australian unconscious.

The Thai resort of Pattaya is a popular destination for Australian tourists. (AAP).

Mr Robb was involved in a fight at the Ruby Club in Pattaya. (Supplied)

Mr Polanco is expected to be held in jail for at least 10 days before an initial court appearance.

If found guilty of Mr Robbs death, the accused could face 15 years jail.

Eyewitnesses said some bars in Pattaya are popular among those involved in weight lifting and martial arts sports in Thailand.

Australian consular officials are helping the family of the man, who are expected to fly to Thailand to retrieve his body.

"The Department of Foreign Affairs and Trade is providing consular assistance to the family of an Australian man who died in Thailand," a Department of Foreign Affairs and Trade spokesman said.