The siege of Leptis Minor (January 46 BC) was a brief attempt by Republican forces under Labienus to recapture a city that had gone over to Caesar soon after his arrival in Africa (Great Roman Civil War).
After their defeat at Pharsalus (48 BC), many of the surviving Republican leaders fled to North Africa, where they rebuilt their strength and soon had a sizable army. Caesar was distracted by events in Egypt, and wasn’t ready to cross over to North Africa until the start of 46 BC.
After his arrival, Caesar became engaged in a standoff with the main Republican army under Metellus Scipio. Despite his apparently weak position, Caesar held his own, and began to win over some of the local communities. Amongst them was Leptis Minor, which submitted to him when Caesar moved his main army towards them. Caesar left six cohorts under Saserna to defend Leptis and returned to his main camp.
While the two main armies were engaged in a series of skirmishes between their lines, Labienus decided to try and recapture Leptis. He first attempted to take the city by surprise with a cavalry attack, but this was repulsed by the garrison.
Labienus made a series of attempts to capture the town, but the siege was lifted after the commander of one of his cavalry squadrons was killed by a crossbow bolt, which penetrated his body and pinned him to his own shield. This so demoralised the rest of his men that they fled and the siege was lifted.