Three opposition figures have pleaded not guilty to charges levelled against them in the Malaysian courts.

Lawyer Karpal Singh, who is acting for the jailed former Deputy Prime Minister Anwar Ibrahim, and opposition leader Marina Yusoff were accused of making seditious remarks.

Another senior opposition figure, Mohamad Ezam Noor, was charged with violating the official secrets act.

Malaysia's sessions court charged Karpal Singh, a long-time critic of Prime Minister Mahathir Mohamad, with sedition after he alleged at Mr Anwar's sodomy trial that "people in high places" had tried to poison his client.

The deputy chairman of the Democratic Action Party pleaded innocent and was released on bail.

If convicted, he faces up to three years in prison and a fine of $1,315.

Crackdown

Karpal Singh was detained in a state crackdown which started on Wednesday with authorities arresting five of the government's most vocal and prominent critics.

On the same day, Mr Mahathir left for a two-week holiday overseas.

Malaysia's Deputy Prime Minister Abdullah Ahmad has denied the arrests mark the start of a widespread crackdown on the opposition.

A court also charged Ms Yusoff, a leader of the National Justice Party, with sedition on Friday.

Prosecutors for the court, in northern Penang state, accused her of trying to incite racial unrest with comments she made during a political speech last year.

In a suburban court outside Kuala Lumpur, Mohamad Ezam Noor, a senior leader of Mr Anwar's National Justice Party, was charged with leaking government documents to the media last year.

All three opposition figures were freed on bail.

On Thursday, the editor and publisher of the Islamic Party's newspaper Harakah, Zulkifli Sulong, pleaded not guilty to sedition in court.

Mr Sulong's publisher, Chia Lim Thye, also appeared in court on a similar charge.

Rallying call

The opposition has called for a mass campaign to persuade the government to withdraw its charges against the five opposition figures.

Karpal Singh said it was the first time in any Commonwealth nation that a lawyer was prosecuted for something said during a court hearing.

He said the case would test the independence of the judiciary and the status of lawyers in Malaysia.

"We propose to take the bull by the horns," he told reporters.

A group of more than 50 Malaysian lawyers have signed a petition calling for an urgent meeting of the country's Bar Council to discuss the case, lawyer P Uthayakumar said.

Malaysia has been in political turmoil since Anwar was fired in September 1998.

His subsequent arrest and corruption conviction provoked massive anti-government demonstrations.

He is now serving a six-year prison term and standing trial for sodomy.

He has denied all the charges against him and says he is the victim of a political conspiracy to destroy both him and the growing movement against Prime Minister Mahathir.