BENGHAZI, Libya — Libya’s transitional leader has declared liberation of the country, three days after the death of its leader of four decades, Moammar Gadhafi.

Mustafa Abdul-Jalil also told thousands of supporters at a ceremony on Sunday that Islamic Sharia law would be the “basic source” of legislation in the country and that existing laws that contradict the teachings of Islam would be nullified. In an address that set an Islamist tone for post-Gadhafi Libya, he said new banks would be set up to follow the Islamic banking system, which bans charging interest.

“This revolution was looked after by God to achieve victory,” he told the crowd.