Attackers used a remote control to detonate the explosives-laden car, which was parked outside a bakery near the city's main hospital, according to Abdel-Salam al-Barghathi, a senior security official. Weapons including Kalashnikov rifles were found inside the car.
Al-Barghathi, the head of the operation room for one of the city's main security agencies, gave the death toll and said 13 people also were wounded in the blast.
There were conflicting reports about the number of causalities.
The Tripoli-based Interior Minister Ashour Shwayel said in an interview with Libya's al-Ahrar TV network that two or three people were killed. Meanwhile, Benghazi police chief Tarek al-Kharaz said at least 13 people were killed and 41 wounded.
The discrepancies could not immediately be reconciled due to the chaotic aftermath and lack of coordination between agencies.
Fathi al-Ubaidi, a top commander of Libya Shield pro-government militias, says one man arrested but refused to give further details.
Benghazi, Libya's second-largest city, was the birthplace of the revolution that led to the death of Gadhafi and it has remained, like rest of the country, largely governed by militias in the absence of unified security and military. They refused to lay down their arms despite efforts by the Tripoli-based central government to impose law and order.
"This is meant to kill civilians and to destabilize the security of the city of Benghazi," he said. al-Barghathi
The city has suffered a series of assassinations and car bombs over the past year as power struggles between militias intensify.
On Sept. 11, The U.S. Ambassador in Libya Chris Stevens was killed along with three other Americans when militias launched two attacks on U.S. mission and another American-run site in the city. Attacks on foreign diplomats led Western countries including Britain to withdraw their nationals from the city.
Copyright 2013 The Associated Press.