At 1 a.m. on Dec. 20, 1970, a minor traffic accident involving a drunken American driver and an Okinawan pedestrian in Koza (present-day city of Okinawa) sparked the largest anti-U.S. riot the prefecture had ever seen.

Prior to the accident, tensions in the city had been high — primarily due to a string of crimes in which the American suspects had gone unpunished as well as media reports of a leak of nerve gas on nearby Kadena Air Base — but nobody could have foreseen the scale of the violence that would erupt that night.

Over 3,000 local residents flooded the streets of Koza, dragging American drivers from their cars, beating them, then burning their vehicles.

At 4 a.m., the crowd stormed the gates of Kadena and set fire to some of its administrative buildings. By the time the last of the rioters dispersed around dawn, more than 60 Americans were hospitalized and over 80 cars were smoldering after being torched.

Among the U.S. reinforcements called in the next day to deter any further violence was Larry Gray, a 23-year-old MP assigned to the 20th Military Police Company. Although Gray had been off-duty the previous night and had missed the riot itself, he wanted to ensure that he did not let slip the scenes of the cleanup operation — so he brought along his camera.

While several Okinawa photographers were also around that day, the 55 images Gray captured are believed to be the only ones to catalogue an American perspective of the riot’s aftermath. At their barracks, ranks of military policemen lined up to listen to their orders. Nervous-looking GIs clutched shields and staves as they guarded the gates of Kadena Air Base. An army truck packed with M16-toting soldiers barreled through the city.

The composition of some of the images rivals that of professional photojournalists, but Gray is quick to dismiss such compliments. “Photography was just a hobby when I was on Okinawa. A way to pass the time. I used to go to the military hobby shop to develop and print the photos,” he said.

This modesty might have prevented Gray’s photographs from ever seeing the light of day; it was only when he was cleaning his attic at his home in Spokane, Washington, last year that he rediscovered them. “For unknown reasons, I had retained a shoe box full of Okinawa photos. A bunch of them were of the Koza riot. I hadn’t looked at them in decades and they were just collecting dust,” explained Gray.

Looking through the photographs rekindled Gray’s interest in the period between 1969 and 1971 that he served in Okinawa, so he headed online to search for information about his MP unit.

Gray soon made contact with a fellow veteran named Bruce Lieber who had also been an MP at the time of the riot. The two never met each other in Okinawa, but, after exchanging email, they found they shared a very personal connection: one of Gray’s photographs showed the burned shell of Lieber’s patrol car.

“I was really surprised to see my old car again. I was one of the first MPs on the scene of the riot. It was really frightening. The crowd surrounded us then they flipped our car and set it on fire,” Lieber told The Japan Times.

Last December, Lieber traveled back to Okinawa on the 40th anniversary of the riot (www.japantimes.co.jp/text/fl20110108a1.html) and donated the brassards from his former MP uniform to Histreet, the city’s postwar history museum. After seeing Gray’s photographs, Lieber was convinced that they deserved to be put on display, too.

“They really impressed me. Especially the photographs of Okinawan demonstrators on the morning after the riot showing their anger with the U.S. military occupation. I had never been aware of that before,” said Lieber.

Lieber’s comments persuaded Gray of the historical value of his images. “If other folks can enjoy and learn from my photographs, then that’s better than just letting them go to waste. So I thought, ‘Why not give them to the museum?’ ” said Gray.

Last month, Gray contacted the Histreet museum and arranged to donate the photographs. Katsumi Ishiki, a member of the city of Okinawa’s history archives section, was delighted to accept the offer.

“The city of Okinawa is really grateful to receive these photographs. Every year, the museum hosts an exhibition related to the riot. This year, we will display these photographs — and for many years to come. It’s important that people . . . remember what happened that night,” said Ishiki.

This month marks the 41st anniversary of the Koza riot. But with Okinawa still host to around three-quarters of U.S. bases in Japan, the riot continues to divide opinion in the prefecture. Some residents believe the riot’s violence contradicts Okinawa’s renowned pacifist tenets; others argue it was a justified act of resistance against an oppressive military regime.

While Gray doesn’t condone the violence of the riot, he said he can sympathize with its roots. “Okinawans got a bad deal at that time. The U.S. needed a military presence in the region to defend both America and Japan. But there was no reason for the entire Island of Okinawa to be controlled by the military. In my mind, the riot was a general statement of resentment against the U.S.”

Gray’s photographs of the Koza riot will be on display at the Histreet museum in the city of Okinawa from Sunday to March 31. Enquiries can be made (in Japanese) at (098) 929-2922.