Pakistan's President Gen. Pervez Musharraf has fired the Islamic nation's chief justice for "misuse of authority," the information minister said.

The firing touched off a protest by a union representing the nation's lawyers. Pakistani security forces wielding sticks and batons attacked the protesters, beating several, witnesses said.

Information Minister Mohammed Ali Durrani gave no further details about why Iftikhar Mohammed Chaudhry, chief judge of the Supreme Court, was sacked. He had served in the post since 2005.

The Associated Press contributed to this report.