The wife of Anwar Ibrahim, the jailed rival of Malaysian Prime Minister Mahathir Mohamad, protested on Tuesday against the arrest of a leading opposition activist who is accused of planning demonstrations to topple the government.
Wan Azizah Wan Ismail, who formed opposition Parti Keadilan Nasional after her husband was arrested in 1998, said activist Ezam Mohd Noor expected to be charged under the Sedition Act on Wednesday.
Ezam is the leader of the youth wing of the party and was arrested on Monday outside Wan Azizah's house.
"We uphold the right to peacefully assemble," Wan Azizah said, adding police tactics at recent gatherings had caused "things to go helter skelter".
In at least two Keadilan gatherings last month the police used water cannon and tear gas to disperse crowds.
"A rally is not part of the party programme it is (an expression) of ordinary people," said Wan Azizah, who attended a rally of over 20,000 people in Mahathir's home state of Kedah at the weekend.
A senior police officer issued a warning on Monday that "demonstrations to inconvenience others or threaten security" will be dealt with harshly.
The spiritual leader of the main Islamic opposition party, Parti Islam se-Malaysia (PAS), which organised the Kedah rally, also blasted the government's clamp down on rights of assembly and media criticism.
"Humans are such that if you try to stop them from voicing their feelings they will find other ways," Nik Aziz Nik Mat said, according to the Sun newspaper.
Ezam and leaders of the other youth wings of parties in Barisan Alternatif (Alternative Front) led by PAS, launched a nationwide campaign on Friday to highlight alleged misuse of public funds to bail out Malay tycoons with ties to government.
"We don't want to ruin the country or frighten people. It is just to raise people's awareness of how our country's coffers are being used," Wan Azizah told Reuters.
"People may be moved to register their protest, because sometimes they are not aware how the country is being run."
Ezam is the highest profile Keadilan leader after Wan Azizah. Formerly, he was Anwar's political secretary.
Observers say he has cultivated a style of dress and speech similar to that of the charismatic Anwar.
The Hari Raya Aidiladha festival on Tuesday could mean Ezam is held longer than the customary 24 hours before being charged, whereupon he could be given bail.
The Youth Wing of Mahathir's United Malay National Organisation (UMNO) lodged a report with the police calling on them to investigate comments by Ezam which were carried in a Malay language newspaper.
He is reported to have said that the opposition party would organise street demonstrations to overthrow the government.
Ezam, in a statement posted on the freeanwar.com website in the early hours of Tuesday, said the report had misrepresented what he was saying.
"The latest series of episodes perpetuated by Utusan Malaysia, an UMNO propaganda organ masquerading as a newspaper, reveals Mahathir's strategy of using the media to create a climate of fear," Ezam said.
Ezam told Reuters two weeks ago the campaign against misuse of funds aimed to mobilise support for a major rally on April 6.
Ezam also said major events would be planned for April 14 to mark the second anniversary of the day Anwar received his first guilty sentence. Ezam said the date would be billed as "Mahathir's Cruelty Day".
Anwar, a former finance minister and deputy prime minister, is serving a 15-year jail sentence for sodomy and corruption convictions, which he says were concocted to forestall a challenge against Mahathir.
Mahathir said his former deputy was immoral and unfit to rule. The U.S. State department describes Anwar as a political prisoner.