MANILA, Philippines (1st UPDATE) - A grenade blast rocked parked cars outside the Tower Inn business hotel along Arnaiz Avenue (formerly Pasay Rd.) in Makati City early Monday morning.

No one was hurt in the incident, but 4 cars in the area were damaged.

Responding firefighters were able to put the flames under control.

In an interview on ANC's Top Story on Monday afternoon, Sr. Supt. Froilan Bonifacio, Makati City Police chief, said they are ruling out terrorism as the motive behind the blast.

He said the perpetrators may either have a grudge against or may be business rivals of the owners of the vehicles parked along Tower Inn hotel.

Bonifacio said the apparent target of the blast was Freddie Calderon, owner of a Toyota Revo, which sustained the biggest damage. Calderon told police he is from Davao and just came to Manila to fetch a relative who was set to arrive from Macau.

Two other vehicle owners were identified as Augusto Palileo and Peter Bantigue.

Bonifacio said these are just angles they are pursuing, adding that "they're still trying to figure out" the reasons for the blast. -- report from ANC