At least 28 people were killed in an attack on a military academy in the Libyan capital late on Saturday, the health minister of the Tripoli-based government said.
Tripoli, which is under the control of the internationally recognised Government of National Accord (GNA), is facing an offensive by military commander Khalifa Haftar's Libyan National Army (LNA) that began in April.
There has been an increase in airstrikes and shelling around Tripoli in recent weeks, with fears that fighting could escalate further after Turkey's parliament voted to allow a troop deployment in support of the GNA.
Forces allied with the GNA described Saturday's attack on the military camp at Al-Hadhba as "an aerial bombing" launched by their eastern rivals. An LNA spokesman denied involvement.
GNA Health Minister Hamid bin Omar told Reuters in a phone call that the number of dead and wounded was still rising. Tripoli ambulance service spokesman Osama Ali said some body parts could not be immediately counted by forensic experts.
Earlier, the ambulance service appealed for a temporary ceasefire to allow its members to retrieve the bodies of five civilians killed on As Sidra Road area south of central Tripoli, and evacuate families living in there.
Emergency teams withdrew after coming under fire while trying to access the area on Saturday, it added.
An increase in airstrikes and shelling in and around Tripoli has caused the deaths of at least 11 civilians since early December and shut down health facilities and schools, the UN mission in Libya said on Friday.
Rockets and shelling also shut down Tripoli's only functioning airport on Friday.
On Friday, UN Secretary-General Antonio Guterres renewed his call for an immediate ceasefire in Libya, warning that the delivery of foreign support to warring parties would "only deepen the ongoing conflict and further complicate efforts to reach a peaceful and comprehensive political solution".
Libya's eastern-based parliament, which relocated from Tripoli in 2014 as the country split into rival camps in Tripoli and the east, voted to provide Haftar with emergency funding on Saturday.
The pro-Haftar chamber also held a series of symbolic votes against the GNA and Turkey, which struck two pacts on maritime boundaries and military cooperation in November.