A father died and his eight-year-old son was seriously injured when an unknown attacker threw a grenade into their home in Kampong Thom province this week.

Police chief of Kampong Svay district Seng Ly said yesterday that the grenade had been thrown into the house in Kampong Kor commune at midnight on Tuesday, killing Chun Heak, aged 46.

An investigation in underway to find the attacker, he said, who struck while the family were sleeping.

The injured boy, Heak Chhun Leng, has been sent to a Siem Reap hospital for treatment. Police said revenge could be a motive for the attack.

Nhoung Samoeun, provincial coordinator for rights group Licadho, said yesterday that the organisation intended to investigate the scene of the attack today. Police officials were trying very hard to protect residents in the area, he said.

Last week, three people were killed and nine others injured in what police believe was a suicidal grenade attack in the Kandal Stung district of Kandal province.