In an emotionally charged speech to about 2,000 supporters after Friday prayers, Anwar vowed to continue a struggle for reform.

"The power is with the people, not with two and three leaders, not with senior officials, not with corporate leaders," said Anwar, dressed in a simple white tunic, sarong and sandals.

Anwar was sacked as deputy prime minister and finance minister on Wednesday, and expelled from prime minister Mahathir Mohamad's United Malays National Organisation (UMNO) a day later.

The 51-year-old politician said on Thursday that he was the victim of a high-level conspiracy and he feared that he would be arrested under the Internal Security Act (ISA) or the Official Secrets Act (OSA).

"The real power is with the people, those who are brave to demand their rights and brave todemand reform and changes. If they keep me under the ISA, God willing, I will go, but hundreds will follow," he said.

"I'm willing to be sued, charged in court."

Fifteen human rights groups and opposition parties signed a joint statement saying they feared the surfacing of allegations of impropriety against Anwar could mean Mahathir planned a crackdown against opponents.

In 1987, more than 100 people were jailed under the ISA.

Police are investigating allegations lodged by seven people who accused Anwar of homosexuality, sexual misconduct and abuse of power.

Anwar has denied the allegations and sued the author of a book containing some of the allegations for defamation.

Anwar, who irritated Mahathir earlier this year when he spoke out against cronyism and nepotism, said he looked to the people for support.

"How long do they want to cling to power? How long do they want to monopolise wealth? How long do they want to cheat the people? Remember man can plan but it is God that decides," hesaid.

His supporters shouted "Allahu Akbar" (God is Greatest) and "Long Live Anwar". At one point as the crowd accompanied Anwar back to his house after the prayers, they lifted Anwar off his feet. Police stood by watching.

When Anwar arrived at his house, he thanked the supporters and said: "I will continue with the struggle."