Libyan authorities said that three men suspected of planning bomb attacks were killed in a sting operation outside the capital.
"The brain of the operation refused to surrender and fought fiercely which resulted in the death of three people, including him," said Saleh Darhoub, spokesman of the ruling National Transitional Council (NTC).
Five members of the interior ministry brigade which carried out the sting operation on Sunday were wounded. The clashes took place in a farm in Al-Aziziya, 40 kilometres (25 miles) south of the capital, he said.
Darhoub told reporters that the explosives found in the area matched those found by security forces who had foiled "seven bombing plots". He declined to give details on possible targets.
The sting operation comes just one day after a gunbattle over market space and a car explosion rocked the centre of the Libyan capital.
Darhoub told AFP that Saturday's car explosion in Tripoli was caused by a bomb crafted out of explosives that are commonly used in fishing.
"It was a local bomb made from gelatina," he said.
On Sunday, armed assailants laid siege to a residence of Red Cross staff in the western Libyan city of Misrata, causing major damage to the building, the organisation said.
NTC spokesman Saleh Darhoub condemned the attack on the ICRC residence.
"We must condemn this as a government and a people," Darhoub said, noting that the ICRC served the country when it was most needed, including when the troops of slain leader Moamer Kadhafi laid siege to Misrata last year.
"We condemn all acts of violence and we condemn extremism", he said, as they were contrary to the moderate Muslim values embraced by the majority of Libyans.
Most of the urban violence to have hit Libya in the wake of last year's revolt which ousted Kadhafi has taken place in the eastern city of Benghazi.