National Transitional Council leader Mustafa Abdel Jalil and other officials attended a ceremony in Benghazi on October 23, which began with a reading from the Koran before being followed with the singing of the national anthem.
National Transitional Council leaders paid tribute to the thousands who died in the eight-month battle to oust Muammar Qaddafi.
Many of those in the crowd waved the new Libyan flag.
The liberation declaration comes three days after Muammar Qaddafi was captured and killed, and more than two months after anti-Qaddafi forces seized the Libyan capital Tripoli.
The National Transitional Council has said the declaration of liberation will lead to the formation of an interim government within a month and elections for a constitutional assembly within eight months, followed by parliamentary and presidential elections.
Acting Prime Minister Mahmud Jibril has announced he intends to resign after the declaration of liberation.
compiled from agency reports