The Libyan capital’s most powerful armed factions battled in several districts overnight and into Tuesday morning in the city’s worst violence this year, raising fears of a wider escalation.

The death toll from escalating clashes remains unclear but a medical unit linked to the defence ministry said it had recovered three bodies from Furnaj, Ain Zara and Tarik Shok districts.

The health ministry appealed to citizens to donate blood to help casualties. Usama Ali, a spokesperson for the ambulance service, said 19 people had been injured.

Dark smoke hung over parts of the city early on Tuesday and the sound of heavy weapons rattled through the streets, a Reuters journalist in Tripoli said. Residents and local media reported fighting in different parts of the capital. The clashes between the 444 Brigade and the Special Deterrence Force, which both backed the interim Government of National Unity during brief battles last year, shattered months of relative calm in Tripoli.