WIRE:04/15/2000 06:36:00 ET

KUALA LUMPUR, Malaysia (AP) _ Security forces surged into Kuala Lumpur's main mosque and fanned out across downtown today, arresting scores of people in an attempt to crush a protest by supporters of Malaysia's ousted deputy prime minister.

Tian Chua, vice president of the opposition National Justice Party, said those arrested included at least 10 rally organizers traveling to the capital for the demonstration in support of jailed politician Anwar Ibrahim.

Witnesses said more people were arrested at commuter train stations to prevent them from congregating at the National Mosque for the rally, which was to mark the first anniversary of Anwar's conviction and sentencing by a High Court to six years imprisonment.

Police carrying truncheons went into the white marble mosque as pro-Anwar supporters began shouting and some tried to wave opposition banners and flags. When the protesters tried to regroup at the mosque, a police truck fitted with a water cannon sprayed them. Police arrested many of the drenched activists.

Several people, some of them handcuffed, were seen being dragged from the mosque. Authorities later sealed the building's entrances. A helicopter circled the area to keep the scrambling protesters in view.

A police officer confirmed that many arrests were made, but declined to give a number.

It was not clear if the protesters planned to go ahead with the march to demand an end to Prime Minister Mahathir Mohamad's 18-year rule. Anwar, 53, was arrested in September 1998, days after Mahathir sacked him and denounced him as a corrupt official, an adulterer and a homosexual. Kuala Lumpur erupted in anti-government protests, but they died out soon after his trial began.

Anwar and his supporters say the charges are a political frame-up to end a challenge he posed to Mahathir.

Police arrested three leaders of the Justice Party on Friday, beginning a show of force to block the protest.

"They are trying to intimidate us with these arrests," said Tian, who is wanted by police for his part in organizing the demonstration.

"It just shows how scared and hysterical Dr. Mahathir has become over a demonstration. That makes us more determined to struggle for freedom and democracy in this country," he told The Associated Press in a telephone interview.

Today's protest was an attempt to demonstrate that despite being behind bars for about two years, Anwar is still popular among Malaysians and seen as a martyr for democracy and political reform.

"Although people may feel cowed by the show of force, nonetheless I get the feeling that they are a lot angrier now than ever before," said Chandra Muzaffar, deputy leader of the Justice Party.

Since the opposition parties improved their strength in Parliament in November's election, Mahathir's government has taken measures to curb dissent.

Opposition newspapers have been restricted or shut down. Authorities began prosecuting several opposition figures and the editor of one opposition newspaper on sedition charges. Public rallies were banned in Kuala Lumpur. Mahathir, senior government officials and the police have repeatedly warned of stern treatment for the protesters.