MANILA - ELECTRICITY was cut in large areas of six provinces in the southern Philippines after suspected separatist guerrillas blew up a key transmission line tower, officials said on Tuesday.

Crude bombs toppled a major transmission line tower in North Cotabato province late on Monday, snapping a 69KV cable supplying electricity to six provinces on the southern island of Mindanao, army spokesman Lieutenant-Colonel Jonathan Ponce said.

'There are strong suspicions that rogue members of the Moro Islamic Liberation Front (MILF) could be behind the latest attack on power facilities in the south,' Lieut Ponce told reporters, adding the toppled tower was in an area where rebels operate.

Lieut Ponce said authorities were also checking reports that rebels have been targeting power facilities in the south to extort money to sustain combat operations against government forces.

In December 2007, the government sold the country's power grid to a consortium led by China's State Grid Corp for US$3.95 billion (S$6.06 billion), which took over the facilities in mid-January this year.

Elmo Batislaong, manager of the National Power Grid Corp in Tacurong City, said it would take weeks before electricity could be fully restored in the south, although local power distributors could shift to emergency generators in key urban centres.

In January, three transmission towers were damaged by blasts causing a month-long power outage in wide areas of the southern Philippines.

Last year, nearly 40 steel towers holding transmission lines were either destroyed or damaged by bomb attacks by Muslim rebels and criminal groups demanding protection money. -- REUTERS