Half a million litres of diesel leaked into Manila Bay, the busiest waterway in Northern Philippines, raising environmental and health concerns, the media reported Friday.

 

 According to the Philippine Coast Guard, the spilled oil has spread to 12 coastal barangays in the province of Cavite and was continuing to spread, reports Xinhua.

 

 "There have been reports of people going to hospital due to difficulty in breathing due to the fumes coming from the oil, " a local official said.

 

 The origin of the incident was being determined by the authorities but it is alleged that the oil leaked from oil tanker MV Makisig, which is commissioned by oil giant Petron.

 

 A 300-sq-km slick made by the leaked oil was drifting toward the mouth of the Manila Bay Friday, reported the web site of Philippine Daily Inquirer.