The prosecutor of the International Criminal Court announced Monday there would be a preliminary probe of possible crimes against humanity committed in Libya, after a referral by the UN.
Meanwhile, France has announced it is sending two planes of aid to Benghazi, which is under the control of protesters and the European Union has imposed travel bans on Libyan President Moamer Kadhafi and 25 others.
The city, which has a population of about a million, is being run by new authorities, appointed on Sunday.
"The situation is a bit confusing; the transition authorities are trying their best to keep the city running," says correspondent Nick Champeaux in Benghazi.
"They want to avoid looting and they're also trying to assist the thousands of foreign nationals, mainly from Sudan, who are stranded here."
Women are bringing food supplies to help people distributing aid and leaflets are being distributed encouraging people to keep the city clean and to refrain from looting.
About 200 Sudanese nationals gathered in front of the Sudanese consulate on Monday, waiting for their passports to try to make it to the Egyptian border, where there is medical aid and other facilities.
"They don't feel secure here because young people raided a military barracks 10 days ago and helped themselves to shotguns," says Champeaux.
He said West African nationals are particularly scared about being mistaken for mercenaries and they are staying indoors.
On Sunday a spokesman for the citiy's transitional authority said there was no room whatsoever for negotiations with Kadhafi.
Doctors in Benghazi have told the International Committee of the Red Cross that 256 people were killed and 2,000 injured in the eastern Libyan city in violence during the uprising, the ICRC said on Sunday.
France will send "massive" aid to opposition territory in Libya and has not ruled out supporting a Nato enforcement of a no-fly zone over the country, Prime Minister Francois Fillon said Monday.
"In a few hours two French planes will leave for Benghazi on behalf of the French government with doctors, nurses, medical equipment and medicine," Fillon told RTL radio.
"This will be the start of a massive humanitarian aid operation to the populations of liberated areas," he declared.
"This means clearly that Paris has chosen its side and that Paris is in contact with the new revolutionary authorities who were created less than 24 hours ago," says Champeaux.
The European Union said Monday that it is trying to establish contact with the Libyan opposition.
The United Nations Human Rights Council met Monday in Geneva to discuss the crackdown by Kadhafi's forces on protests and the ensuing humanitarian crisis.
UN high commissioner for human rights, Navi Pillay warned that the threat of violent reprisals against civilians remains, and that the council should closely monitor the situation.
The European Union on Monday agreed to impose an asset freeze and travel ban on Kadhafi and 25 members of his family and inner circle, officials said.
The package of sanctions includes an arms embargo as well as a ban on providing Tripoli with law enforcement equipment that might be used to crack down on protesters.
"What is going on -- the massive violence against peaceful demonstrators --
shocks our conscience," the EU's foreign policy chief Catherine Ashton said. "It should spring us into action."
The sanctions decided by the 27-nation bloc will come into force in several days.