QUEZON CITY, Philippines -- A mysterious explosion occurred near the foot of an electric post on Access Road, Area 4 Extension, Spring Country in Barangay (village) Bagong Silangan, in Quezon City, at around 4 a.m. Saturday, police said.

Senior Superintendent Neri Andal Ilagan said in an official report that no one was reported hurt in the explosion, which left a crater measuring 3 feet and 3 inches in diameter and 1 foot and 6 inches deep.

?We still don?t know what caused the explosion and we are still gathering explosive components,? Ilagan told the Inquirer.

He added that elements from the district?s Explosive Ordnance Division led by Inspector Sheryl Ballete, who were conducting a post-blast examination, had collected soil samples to determine the kind of explosive used.