Muslim hardliners chopped up a 100-year-old banyan tree in Jakarta to halt a rumour about its special powers from spreading, officials in the Indonesian city said Tuesday.

"Surely, no one can believe that a tree is more powerful than a human," Zainal Arifin, the leader of the Muslim group that admits to attacking the tree, was quoted as saying by Detik.com news website.

"We did this to propagate Islam."

Islam is a strongly monotheistic religion, and believing in any power other than God is considered a grave sin. Hardliners in Indonesia often criticize other Muslims for still practising Hindu, Buddhist and animist rituals that predate Islam's arrival in the archipelago.

The sprawling tree's branches were hacked away Sunday, leaving just its trunk, said Sarwo Handayani, head of the city's park agency. She said it was too early to say if the tree will survive.

Earlier, rumours had spread that cutting down the tree would bring bad luck because it was spared during a tree-felling drive to make way for a new bus lane in central Jakarta, Handayani said.

She said the rumours gained strength after unidentified people left offerings at the tree's base.

Handayani dismissed the rumours of supernatural involvement as nonsense, saying officials did not fell the tree because the bus lane could be routed around it.

"This was an outrageous act," she said of the damage to the tree, adding that the city had reported it to police on Monday as an act of vandalism.

Arifin said the fact that nothing supernatural happened to the Muslims who attacked the tree proves that it has no mystical powers.