News of the death of two children came hours after Amnesty International accused both sides of "utter disregard" for the laws of war, in a report citing possible war crimes.
Two children were killed on Tuesday when a rocket hit their home in Libya's capital Tripoli, as Amnesty International accused warring parties fighting for the city of "utter disregard" for the laws of war.
The UN-recognised Government of National Accord (GNA) blamed the strike on the forces of east Libyan warlord Khalifa Haftar.
Haftar launched an offensive to take the capital in April, but met fierce resistance from forces loyal to the Tripoli-based GNA.
GNA Health Ministry spokesman Al Amin al Hachemi told AFP that three other family members — both parents and another child — were wounded when the rocket hit their home in the southern Tripoli residential neighbourhood of Salaheddine.
A spokesman for Haftar's forces, Ahmad al Mesmari, reported air strikes on military sites and "arms depots" on Tuesday, without giving further details.
News of the deaths came hours after Amnesty International accused both sides of "utter disregard" for the laws of war, in a report released on Tuesday, citing possible war crimes.
"Warring parties ... have killed and maimed scores of civilians by launching indiscriminate attacks and using a range of inaccurate explosive weapons in populated urban areas," the rights watchdog said.
"Both sides have shown utter disregard for the fundamental principles of international humanitarian law (the laws of war), which forbid such attacks," the report added.
UNICEF said in a statement on Tuesday that seven children have been killed in the conflict in two weeks, not including those on Tuesday.
"Children are not a target and should be protected at all times wherever they are," the statement said.
UNICEF urged both sides to "refrain from attacks on civilian infrastructure including people’s homes, schools, hospitals and medical facilities."
Fighting has caused at least 1,093 deaths and 5,752 injuries, among them dozens of civilians. More than 128,000 people have fled their homes, the United Nations reported in July.
Amnesty said it had investigated on both sides of the frontline, finding "a systematic disregard for international law, fuelled by the continued supply of weapons to both sides in violation of a UN arms embargo."
Arms exports to Libya have been banned since the 2011 revolt to overthrow dictator Muammar Gaddafi.
"Scores of civilians have been killed and injured as both sides use everything from Gaddafi-era unguided rockets to modern drone-launched guided missiles in attacks that could amount to war crimes," said Amnesty researcher Brian Castner.
Amnesty said it had visited 33 attacked sites around Tripoli, including an airport, schools and field hospitals, finding evidence of possible war crimes by both sides.
The most lethal attack documented was a missile strike in July on a field hospital that killed five medics and rescuers as well as injured eight others.
Amnesty established that the missile was fired from a Chinese Wing Loong drone, which the United Arab Emirates operates for pro-Haftar forces.
"The international community must uphold the UN arms embargo, which Turkey, the UAE, Jordan and other countries have flagrantly violated," Castner said.