MANILA, Philippines -- Two men were hurt when an unidentified man lobbed a grenade into a house in Pasay City, Saturday night.

Victims Arnel Villaruel, 32, of Daop Palad Street, Balagbag in Merville, and Antonio de Jesus, 35, of Kalayaan Village, sustained shrapnel wounds in the explosion at Villaruel's home around 9:30 p.m. on Saturday.

Both were taken to the hospital for treatment.

Initial investigation by SPO1 Joel Landicho showed that the victims were drinking inside the house when an unnamed man passed by and suddenly threw a US fragmentation grenade at them.

Senior Superintendent Raul Petrasanta, the Pasay police chief, said they were eyeing revenge as a possible motive since Villaruel had known enemies.