A Cambodian appeals court has refused to release on bail 21 people arrested early last month in connection with anti-government protests.

The detainees are garment workers and rights activists arrested during protests focusing on demands for a higher minimum wage for factory workers. Al least four people were shot dead by police during the protests.

Defense lawyer Sam Sokong told reporters that judges said the court feared that if these detainees were freed pending trial, it would affect public order and make it harder to conduct investigations. He said he would appeal the ruling to the Supreme Court.

The protests and opposition demonstrations calling for new election pose the biggest challenge in years to authoritarian Prime Minister Hun Sen's rule.