A relatively unknown disaster at Pearl Harbor during World War II that killed or injured more than 560 U.S. soldiers was commemorated Friday in a ceremony at the National Memorial Cemetery of the Pacific at Punchbowl.

The West Loch Disaster, sometimes known as the “second Pearl Harbor,” involved a munitions accident that took place nearly 80 years ago on May 21, 1944, when a chain of explosions and fires killed or injured hundreds of soldiers, destroyed ships loaded with fuel and ammunition, and damaged nearby buildings.

It’s considered the second- worst disaster at Pearl Harbor, in terms of casualties, behind the Japanese attack on Dec. 7, 1941, which killed more than 2,400 U.S. service members and civilians.

The Obama Hawaiian Africana Museum, in colla­boration with Hawaii Joint Military Forces, hosted a celebration of life for the soldiers who perished in the West Loch Disaster, more than half of whom were Black Americans from the 29th Chemical Decontamination Unit.

Keynote speaker Maj. Gen. David Wilson said those who died must be remembered for their heroism.

“The West Loch Disaster remains an important part of World War II history,” Wilson said. “It should be shared to honor the lives of those that were lost. Their service and their sacrifice must never be forgotten.”

Soldiers from Schofield Barracks were loading ammunition and fuel onto football field-size landing ships at the West Loch peninsula in Pearl Harbor in preparation for the invasion of Saipan when a chain reaction of explosions and fires that lasted 24 hours killed more than 160 soldiers and injured nearly 400 others.

One of the ships exploded, and the resulting shrapnel, flames and spilled fuel sparked fires that spread to nearby ships, destroying six vessels.

Some of those who died during the incident have not yet been identified. Dozens of body parts recovered from the disaster were interred at the National Memorial Cemetery of the Pacific without names or unit designations, but efforts to identify them are ongoing.

It’s still not entirely clear what caused the first ship to explode, but the incident was kept classified as top secret to protect the scheduled invasion. The Obama Hawaiian Africana Museum is hoping to increase awareness of the incident and remember the soldiers injured or killed in the tragedy.

Speaking at Friday’s ce­remony, Tom Leatherman, superintendent of the Pearl Harbor National Memorial, said the West Loch Disaster was similar to the munitions explosions of the Port Chicago Disaster in California, which took place two months after the Hawaii accident, and both are important but relatively unknown events in American history.

“Understanding the full history and context of these disasters is the only way we can truly honor those who have lost their lives,” Leatherman said.