This is the shocking moment the back of a passenger bus exploded after a suspected bombing incident in the Philippines today.

The occupied vehicle was driving along a road in front of a shopping mall in Koronadal City, South Cotabato province shortly after noon on May 26 when the alleged explosive was detonated, sending pieces of debris flying across the street.

At the time of the blast, there were four passengers inside the bus, as well as the conductor and the driver. Local media said all of them were safe, but two tricycle drivers tailing the bus were reportedly wounded.

Rolly Doane Aquino, head of the South Cotabato Disaster Risk Reduction and Management Office, said in a video statement following the incident: 'As of now, there are teams deployed from the Philippine National Police, the provincial disaster management office, the Bureau of Fire Protection, and other emergency respondents.

'Currently, we have confirmed that there were victims. They have already been sent to the hospital. We have to be careful and vigilant about our surroundings. We also urge everyone to report to proper authorities any suspicious activities they may see.'

Bernard Bolanio, operations manager of the company that owns the bus, said he could not think of a motive for the explosion as they have not received any threats.

Local police are now at the scene to investigate the incident.