An Australian academic has uncovered what he believes is evidence of a mutiny by African-American soldiers stationed Down Under during World War II sparked by racial abuse.

James Cook University historian Ray Holyoak has been researching why then United States Congressman Lyndon B. Johnson visited the northern Queensland town of Townsville for three days in 1942.

"For 70 years there's been a rumour in Townsville that there was a mutiny among African-American servicemen," Holyoak told ABC Radio.

"In the last year and a half I've found the primary documentation evidence that that did occur in 1942."

Queensland was a significant support base for soldiers serving in the south west Pacific campaign between 1942 and 1945 -- hosting airfields, camps, factories and housing medical facilities.

Holyoak said documents from the era reveal that some of a group of 600 African-American troops sent to Townsville in 1942 to build an airfield ended up involved in a siege in which they turned their guns on their white officers.

"After some serial abuse by two white US officers, there were several ring-leaders and they decided to machine gun the tents of the white officers," he told the state broadcaster.

By poring over the archives of the Queensland Police and the Townsville Brigade, Holyoak said he has discovered that one person was killed and dozens badly injured during the siege at a base on the outskirts of the city.

Soldiers from the US 96th Engineers were stationed at the base which was forced to call in for help from Australian troops, the ABC said.

Holyoak said the siege lasted eight hours during which the mutineers fired machine guns and anti-aircraft weapons into tents where their fellow Americans were drinking.

The historian said the incident was never reported, but he had found a report on it written by an American journalist embedded with the troops, Robert Sherrod.

"I think at the time, it was certainly suppressed," Holyoak said.

"Both the Australian and the US government would not have wanted the details of this coming out. The racial policies at the time really discluded people of colour."

Holyoak intends to continue his research, looking into the sentences given to those involved in the dramatic incident, the ABC said.