Rocket fire forced the suspension of all flights into and out of Tripoli's sole functioning airport on Wednesday, Libya's embattled UN-recognised government said.
Mitiga airport had only reopened early last week following a truce in nine months of fighting for control of the capital with forces loyal to a rival administration based in the east.
Six military-grade Grad rockets targeted the airport in what government forces spokesman Mohammed Gnunu branded a "flagrant threat" to the safety of air traffic and a "new violation" of the ceasefire.