The head of Libya's transitional government urged thousands of cheering supporters in the capital, Tripoli, late Monday to support a civil, democratic state that honors Islam and respects the rule of law.

The chairman of the National Transitional Council, Mustafa Abdel Jalil, said his provisional administration seeks a state where “Islamic law is the basis for legislation,” but rejects any extremist ideology “on the right or the left.”

Jalil arrived in Tripoli Saturday for the first time since his allies chased former leader Moammar Gadhafi out of the city. He addressed the rowdy crowd in Martyrs' Square, a site that until recently was used for pro-Gadhafi rallies. Jalil had been running the provisional government from the eastern city of Benghazi, cradle of the revolt that overthrew Mr. Gadhafi last month.

Jalil also called on Libyans to avoid reprisal attacks against Gadhafi holdouts, saying Libya's judicial system should alone administer justice to those “who harmed the Libyan people.”

In a report released Tuesday, Amnesty International said both sides of the conflict have committed war crimes during the six-month civil war. The report mainly details crimes against civilians committed by Gadhafi loyalists, but also documented brutal revenge crimes committed by some provisional authority forces when loyalist fighters were ejected from eastern Libya.

Forces loyal to Mr. Gadhafi launched a series of counterattacks early Monday, including a surprise raid that killed 15 guards at a key oil refinery in the coastal city of Ras Lanuf, deep inside NTC-controlled territory. Battles also continued near Mr. Gadhafi's hometown of Sirte and in parts of the oasis city of Bani Walid, southeast of Tripoli.

Also Monday, China officially recognized the NTC as the “ruling authority and representative of the Libyan people.” Algerian officials said late Sunday they would recognize the NTC as Libya's rightful authority once a “representative government is in place.”

Moammar Gadhafi's whereabouts is still unknown. Late Saturday, Guinea Bissau's prime minister said his country would welcome the ousted leader should he seek exile in the West African country. Guinea Bissau had strong ties to Mr. Gadhafi's government when he was in power.

A message attributed to the former leader Monday urged Libyans to press ahead for his cause and not to surrender the nation to what he called “colonialism” and “foreign influence.”