Former Umno supreme council member Saifuddin Abdullah says the Security Offences (Special Measures) Act (Sosma), which was used against Umno leader Khairuddin Abu Hassan, is now being used to silence party members from speaking up against the prime minister.

"Sosma has been used against Khairuddin simply because he is a politician from Umno. Top leaders from Umno want to make sure he shuts his mouth and to use it to strike fear in Umno members," Saifuddin said.