THREE unidentified men in motorcycles have been tagged as suspects in the grenade blast at a car manufacturer?s showroom in The Fort, Taguig City, on Tuesday that left a woman wounded.

Police said the suspects were caught by security cameras just seconds before an explosion rocked the Hyundai store on 5th Avenue and 28th Street past 7 p.m. on March 3.

?We saw them in the area just before the grenade explosion,? Taguig Police Chief Camilo Pancratius Cascolan said.

?We are carefully reviewing this footage and all evidence at hand for the immediate resolution of this case.?

Footage from the Tag Watch Command Center, the nerve center of the city government?s elaborate security and surveillance system, showed three men on two motorcycles crossing 5th Avenue and 28th Street at 7:13 p.m. on Tuesday.

After a 360-degree turn and 46 seconds later, the camera showed the Hyundai showroom after the explosion, with a motorcycle still outside.

A fourth man whom investigators believe might have been a lookout was also caught on camera walking along 5th Avenue, a few meters away from the Hyundai store.

The man was acting suspiciously and seemed to have been observing the blast site from afar, Cascolan said.

He said the grenade attack seemed to be an isolated incident and not an act of terrorism.

?We are looking into three possible motives,? Cascolan said.

?It might have been a labor dispute or something done by a thrill seeker?or a diversionary tactic made by criminal elements.?

He cited unconfirmed reports that several Hyundai employees were recently suspended, and that they might have taken revenge against the management.

The blast wounded housemaid Jane Pansoy, 22, who was hit by shrapnel in the leg while she was walking her employer?s dog near the showroom. She has been pronounced out of danger. The dog was not hurt

A passing Toyota Vios sedan driven by one Amelita Alba also had one of its passenger windows shattered, though Alba was not hurt.

Police recovered nine pieces of shrapnel and parts of the fuse assembly and safety lever of an Mk-20 fragmentation grenade, which is commonly used by the military.

No cars in the showroom were damaged.

Cascolan said a crater on the ground near the damaged left front glass of the showroom was the center of the explosion. Ferdinand Fabella