A Malaysian court charged 29 people, including a teenage boy, for taking part in a massive weekend protest against internal security laws that saw 589 people arrested.

 
On Saturday, during the biggest demonstration in Malaysia for nearly two years, police used tear gas and water cannon to disperse at least thousand people calling for the abolition of laws that allow for detention without trial.
 
Most of those detained were released over the past two days but the 29 still in custody were charged at a Kuala Lumpur court with taking part in an illegal rally or aiding an illegal organisation.
 
The detainees all pleaded not guilty and were released on bail. If convicted, they could be jailed for between one and three years, depending on which of the two charges they face.
 
In Malaysia it is illegal to hold a demonstration without a permit from police, who rarely give them the green light. Critics say Prime Minister Najib Razak used the protest to show his political strength.
 
The ISA, derived from British-era laws, was used against an ethnic Chinese communist insurgency from the 1940s. Although now largely used against suspected Islamic militants, critics fear it could be used again to stifle dissent.
 
The ISA has been used against politicians accused of fomenting racial discord, a sensitive issue in a country where the majority is ethnic Malay but with significant ethnic Chinese and Indian minorities. The ISA, coupled with sedition laws and licensing requirements for newspapers, equip Malaysia's government with a formidable arsenal to clamp down on dissent.
 
When Najib Razak, son of Malaysia's second prime minister, was appointed the new prime minister in April, he released Indian rights activists from ISA detention and pledged to review the law, but has yet to act. The opposition, which has painted Najib as a hardliner, says the weekend clampdown shows he will not allow any challenge to the government that has ruled this Southeast Asian country for the past 51 years.
By showing a firm grip on law and order issues, Najib can placate Malays and his United Malays National Organisation (UMNO) party, which is the linchpin of the ruling coalition.

Despite use of repressive measures, the government has survived largely by delivering economic growth, strong leadership and by making opportune alliances to stay in power.
Even the furore whipped up over the Anwar trial, and by the recent death of an aide to an opposition legislator after being questioned by a government body, does not appear to have generated mass support for opposition rallies.

That said, Saturday's protest sends a signal that Anwar remains the biggest threat to the government and the opposition is willing to risk mass arrests to stay in the public eye.