GOMA, Democratic Republic of Congo (Reuters) - Suspected Hutu militiamen killed 16 people, including 12 rangers, on Friday in eastern Democratic Republic of Congo’s Virunga National Park, a government official said, in the deadliest such attack in Virunga’s recent history.

Around 60 fighters from the Democratic Forces for the Liberation of Rwanda (FDLR) ambushed a convoy of civilians that was being protected by 15 rangers, said Cosma Wilungula, director of the Congo Institute for Nature Conservation (ICCN). Many others were seriously injured, he said.

Virunga sits on the forest-covered volcanoes of central Africa and is home to over half the global population of mountain gorillas. It is Africa’s oldest national park and largest tropical rainforest reserve, covering 7,800 sq km (3,000 sq miles).

“The guards were not the target and died while assisting the civilian vehicle that had been caught under fire from the attackers,” the Virunga National Park said in a statement.

The FDLR has waged a periodic war with the Congolese government and rival militias since it was founded in 2000 by Hutu officials who fled Rwanda at the end of the genocide.

The group has been engaged in intense fighting with the army near the site of the ambush in Rumangabo since mid April and often retaliates by attacking civilians, said Kivu Security Tracker (KST), a research initiative that maps unrest in the region.

Almost 200 Virunga rangers have died in past militia attacks. Two years ago, five of them were killed by Mai Mai militiamen, in the deadliest attack at the time.

In May 2018, the park was closed after foreign tourists were kidnapped and their guide killed by gunmen. It reopened in February 2019.