MANILA, Dec 1 (Reuters) - Philippine security forces arrested a leader of the communist rebel movement near a shopping mall in the capital, army and police officials said on Saturday, in a big blow to the Maoist-led guerrilla group.

Elizabeth Principe was head of the northern branch of the New People's Army (NPA) and is married to Leo Velasco, the NPA's leader. His whereabouts are unknown.

"It was a legitimate arrest," Lieutenant-General Alexander Yano, the army commander, told reporters after presenting Principe to the media at a base in the capital. She was captured on Wednesday.

"This is a big blow to the rebel movement and would certainly derail their plans to step up ideological, political and organisational work in urban centres in the country.

"She has at least six arrest warrants for kidnapping, robbery, arson and murder from her rebel activities in northern Philippines."

The 6,000-member NPA, active in 69 of 81 provinces, has been fighting for nearly 40 years to overthrow Manila's democratic government and replace it with a Maoist system.

The conflict has killed more than 40,000 people and, despite the collapse of many communism regimes around the world, continues to thrive in the Philippines because of a yawning gap between a tiny elite and the mass poor.

Last month, a classified army report seen by Reuters said the Philippine military has had limited success in destroying the firepower of communist insurgents, putting it way behind a target of wiping out the rebellion by 2010.

President Gloria Macapagal Arroyo, who is also commander-in-chief, has said she wants the NPA largely defeated by the time she steps down from power in June 2010. (Reporting by Manny Mogato, editing by Carmel Crimmins)

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