Manila, Feb. 6 -- A two-minute minor explosion occurred at the summit crater of Kanlaon Volcano at 3:11 p.m. Thursday, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.

"That minor explosion was likely triggered by a sudden release of pressure within the volcano. This happens when volcanic gases accumulate beneath the surface due to a blockage in the volcanic vent," Phivolcs Director Teresito Bacolcol told the Philippine News Agency.

There was blockage in the volcano's conduit and over pressurization resulted in minor explosion, he added.

A minor explosion, Bacolcol said, is a small, short-lived volcanic event that is much less intense than a major eruption.

"It typically lasts only a few seconds to a few minutes...