The son of Libyan leader Moamer Gaddafi warned against conspiracies targeting his country, as anti-government protests spread to the capital, Tripoli, dpa reported.
Speaking on Libyan TV late on Sunday, Saif al-Islam Gaddafi, warned of conspiracies that might take the country into civil war, and accused the opposition of trying to break up the country.
Emboldened by the successful revolutions in Tunisia and Egypt, thousands of Libyans have been calling for the ouster of Gaddafi, who has been in power for 41 years.
"Libya is not Tunisia or Egypt," Saif al-Islam said, warning protests could break apart the country and lead to chaos.
Clashes had reportedly erupted in the capital Tripoli late Sunday between anti-government protesters and Gaddafi supporters, witnesses said after the capital was dominated by pro-Gaddafi marches over the past days. Earlier anti-government protests were centred in the second largest city of Benghazi.
Dozens of people have been arrested in Libya over the past few days, the official news agency JANA reported. They are accused of belonging to a "foreign network" and seeking to destabilize the country and the people's national unity.
Those arrested included Tunisian, Egyptian, Sudanese, Turkish, Palestinian and Syrian citizens.
Earlier on Sunday, a group of lawyers and judges held a demonstration to express their rejection of the use of violence against protesters over six days of demonstrations.
The London-based news website Libya al-Youm said the army had used rocket-propelled grenades and other heavy weapons on protesters.
Saif al-Islam admitted there had been "mistakes" by police and military forces, who were not trained to deal with crowds. However, he rejected reports of the increasing death toll across the country, saying the figure had been exaggerated by media.
Rights groups said around 150 people had been killed since protests began six days ago. However, doctors and opposition said 200 people were killed in the eastern city of Benghazi alone after the army used heavy weapons on protesters there.
"All young, all unarmed," a doctor in the city said describing the bodies, adding that bodies had been shot either in the head or chest.
With journalists barred from travelling to Benghazi, obtaining reliable information about the situation in the country ruled by Gaddafi since 1969 is difficult.
Al Jazeera TV reported that protesters in Benghazi have reportedly seized army vehicles and weapons after days of violent clashes with the army, dominated by mercenaries.
Others said protesters now control Benghazi, the second largest city after the capital Tripoli, as security forces flee to the airport.
Libyans have been calling on people in neighbouring countries, to pass on medical supplies and mobile phones through the borders. Another witness said hospitals in Benghazi faced a shortage of blood supplies, as he spoke of "a massacre" in the city.
Malcolm Smart, Amnesty International's director for the Middle East and North Africa said: "It looks like Libya's leader may have ordered his forces to put down the protests virtually at any cost, and that cost is being paid in the lives of Libyans."
One witness told the German Press Agency dpa that many soldiers were not Libyans but rather mercenaries from Mali. Another said that foreign troops, from Chad, Senegal, Zimbabwe, made up part of the forces sent to the cities.
Though witnesses have described some forces as "thugs" loyal to Gaddafi, witnesses and opposition groups said that almost half the troops sent to the city had joined the protesters on Sunday.
Libya's ambassador to China, Hussein Sadiq al-Musrati, resigned in protest on air with Al Jazeera Arabic channel. He called on the army to intervene, and called on all diplomatic staff to resign.
Libya, a major oil producer, has a population of about 6 million people.
Protesters around the world have staged protest in solidarity with demonstrations in Libya. In Egypt, a group gathered in front of the Libyan Embassy in Cairo chanting "Egyptians and Libyans are one hand."
The European Union and United States called on Libya's government to refrain from using force against peaceful demonstrators and address its people's demands for reform.
Libya responded by threatening to stop cooperating with efforts to try and stop illegal migrants heading to Europe.