Nigeria's Plateau state government has extended a curfew in the state capital Jos and surrounding areas after signs of increasing tension in the city.

It follows the killing of at least 23 Muslim travellers returning from a religious ceremony - the deadliest violence in the state capital in several years.

Dozens of others were wounded when their convoy of buses was attacked on Saturday in the volatile city.

The Plateau state government said the imposition of curfew was necessary to avoid a further deterioration of the security situation.

The victims were returning to southern Nigeria from the northern city of Bauchi where they had attended a ceremony marking the Islamic New Year.

Their vehicles were intercepted and smashed by a mob using machetes, sticks and rocks.

At least 20 suspects have been arrested. Police blame the violence on youths from Iregwe community who are mainly Christians.

Nigeria’s Plateau state has seen more than a decade of deadly ethnic and religious clashes since 2001 - before the conflicts subsided in recent years.

It comes as insecurity across Nigeria continues to worsen.