MANILA, Philippines - A campaign manager for deposed Philippine leader Joseph Estrada's opposition party was shot and wounded Sunday in the latest eruption of violence ahead of May elections, police said.

Gunmen on a motorcycle ambushed Gerardo Limlingan, 68, as he drove in a Manila suburb. Police said he suffered wounds to his arms and legs and was immediately rushed to a nearby hospital.

Police said the attack appeared to be politically motivated.

Limlingan is the campaign manager of Jejomar Binay, a candidate for vice president running alongside Estrada, who is seeking to return to the presidency nine years after he was ousted by a military-backed popular revolt.

"The attempt on his life is a despicable act that deserves condemnation. It is obviously politically motivated," Binay said in a statement, describing Limlingan as a "dear family friend".

The ambush was the latest in a rash of political attacks ahead of the election, which security experts have warned could be the bloodiest in Philippine history.

Fifty million voters are set to go to the polls on May 10, when 17,000 posts from president down to municipal council seats will be contested.

Many local politicians are known to control private armies, which they use to intimidate or attack rivals. More than 90 people have already been killed in the run-up to the elections, one security group had earlier estimated.

This includes 57 people who died in November, when a Muslim clan that was then closely allied to President Gloria Arroyo allegedly systematically murdered them in southern Maguindanao province.