The Candlelight Party will hold a memorial service in Phnom Penh on Friday for the victims of a 1997 grenade attack that left at least 16 dead and more than 120 injured, including former opposition leader Sam Rainsy.

Four American-made grenades were lobbed into a group of Khmer National Party supporters, at the time led by Rainsy, who were rallying at Wat Botum to call for an independent judiciary. Rainsy only narrowly escaped the resulting carnage.

Candlelight Party official and former Senator Yu Seangheng said Phnom Penh City Hall had granted the party – the renamed remnants of the Sam Rainsy Party – permission for around 100 people to congregate at Wat Botum Park on Friday, where a small memorial to the victims of the attack is located.

“It is just a small event, and is nothing related to politics. It is a religious ceremony," Seangheng said. "There will be no speech and nothing other than religion.”

While a local investigation into the attack yielded no results, the US Federal Bureau of Investigation also conducted an inquiry since an American national was injured in the attack. The investigation was ultimately inconclusive after being curtailed because then-US Ambassador Kenneth Quinn was reluctant to sour relations with Prime Minister Hun Sen.

This will be the opposition’s first public event since the arrest of former Cambodia National Rescue Party President Kem Sokha on treason charges in September and the forced dissolution of the party in November.

Updates to follow