The city of Shimabara, Nagasaki Prefecture, commemorated Friday the 43 victims of a huge pyroclastic flow that 25 years ago spewed from Mount Unzen's Fugen Peak.

Fugen Peak erupted on Nov. 17, 1990, for the first time in around 200 years and caused a massive pyroclastic flow — a fast-moving current of superheated gas, ash and rock — at 4:08 p.m. on June 3, 1991, when the lava dome was breached.

At a memorial service, held by the municipal government for the first time in five years, attendees including bereaved family members of the victims offered a silent prayer and flowers.

Shimabara Mayor Ryuzaburo Furukawa paid tribute to those who "died doing their job."

The victims included reporters, police officers and firefighters. American volcanologist Harry Glicken and French volcanologists Maurice Krafft and his wife Katia were also killed.

Local governments set up an evacuation zone, forcing up to 11,000 people to abandon a residential area.

Another person was also killed by a pyroclastic flow from Fugen Peak on June 23, 1993.

"We can rebuild from disasters at any cost," Furukawa said during the service, in a reference intended to include the powerful earthquakes that struck nearby Kumamoto Prefecture in April.