SEOUL - Tens of thousands of South Korean Buddhists rallied on Wednesday in central Seoul in protest at alleged pro-Christian bias by the government of President Lee Myung Bak.

A crowd estimated by police at 55,000, including thousands of grey-robed monks, packed City Hall Plaza for the rare protest which began with the beating of a giant drum.

Organisers said Buddhist temples across the country rang bronze bells simultaneously.

'Buddhists united to stop religious bias,' read one banner.

A police search involving Jigwan, head monk of the country's main Jogye Buddhist order, was the trigger for the mass rally.

'This is only the beginning of our struggle,' said Jinhwa, a monk acting as spokesman for the organisers.

'This is the first time all 27 (Buddhist) orders have held a rally,' he said, reiterating demands for an apology from Lee, the resignation of police chief Eo Cheong-Soo and legislation formally banning religious discrimination.

Buddhists have been uneasy over what they see as Christian bias since Lee, a Presbyterian church elder, came to power in February. They were unhappy when he included members of his church network in his first cabinet.

An online map published by two ministries, showing Seoul's churches but not major Buddhist temples, also sparked anger.

In early July, seven activists wanted by police following protests against US beef imports took refuge in Seoul's Jogyesa temple.

Tensions grew late last month when police stopped a car carrying Jigwan outside the temple and searched the boot.

Police chief Eo apologised and disciplined two senior officers. But Buddhists accused police of treating the head monk like a criminal and called for Eo's resignation.

The government has tried to placate the Buddhists, with culture minister Yu In Chon expressing regret on Tuesday at the dispute.

Mr Yu said regulations would be introduced to ban religious discrimination by government officials. Mr Lee has urged his officials not to make controversial remarks on matters of faith.

But Buddhists were unappeased. Spokesman Jinhwa said that if their demands are not met, they would hold more protests across the country.

Official data shows South Korea has about 10 million Buddhists and 13.7 million Christians.

'This government is trying to evangelise the whole country and turn it into a Protestant state,' said protester Suk Jin Heung, carrying a banner demanding the resignation of the police chief.

He said many Protestant leaders were under the illusion that the country became a Protestant state when Mr Lee was elected.

'But Lee must know he is not president only for Protestants but for Buddhists and Catholics too, and unbelievers as well,' Mr Suk said. -- AFP