Residents say shelling was among hardest since warring sides agreed on a ceasefire in January. Meanwhile, UN says bombing of civilian neighbourhoods "may amount to war crimes".
Bombardment of the Libyan capital Tripoli intensified on Friday, residents said, forcing the evacuation of some patients from a hospital near the capital's only functioning airport and prompting condemnation by the United Nations.
Residents said the shelling was among the hardest since the two sides said they had agreed a ceasefire in January, as blasts of artillery echoed in the city centre and black smoke billowed near Mitiga airport held by the government.
The fighting, between the illegal militia of warlord Khalifa Haftar and the internationally recognised Government of National Accord (GNA) based in Tripoli, came as the United Nations tried to hold peace talks in Geneva.
Shelling of Mitiga airport, held by the GNA, has forced a suspension of flights for hours at a time on consecutive days this week and new damage to a hangar was visible after Friday's bombardment.
The town council of Abu Salim, a Tripoli neighbourhood also held by the GNA, posted pictures of damaged houses on Facebook, saying a woman and child had been taken to hospital.
The bombing of civilian neighbourhoods of Tripoli "may amount to war crimes", the United Nations' Libya mission said in a statement.
The mission also condemned an attack on Thursday that it said killed five members of a single family in an area held by the LNA, which has attributed the blast to a drone strike.
Haftar began his attack on Tripoli last year in the latest round of fighting in Libya since the 2011 toppling of strongman Muammar Gaddafi.