Just three days ago, the death toll stood at 58 people, including six civilians, and another 275 wounded, according to the WHO.
"#LibyaCrisis casualties are 682: 121 dead and 561 wounded. WHO sending medical supplies, health staff support for first- and second-line responders", the WHO in Libya tweeted late on Saturday.
The health organisation also condemned the attacks on health care workers, noting that a total of eight ambulances had come under fire since the beginning of the Tripoli offensive.
"Two more ambulances were struck in #Libya Saturday during the #Tripoli fighting, bringing the total number to 8 since the violence began. WHO strongly condemns repeated attacks on health care workers, vehicles", the WHO added.
The security and political situation in Libya has been unstable ever since a 2011 revolution, as the country is still divided between two authorities, with the LNA-backed parliament in Tobruk ruling over eastern Libya and the GNA controlling the west of the country.