The government of the northern Chinese region of Ningxia has punished 11 officials for dereliction of duty after a deadly bus fire last year killed 18 people in the regional capital Yinchuan.

The man blamed for starting the fire, Ma Yongping, was executed in December. He set alight two plastic bags filled with gasoline on the bus after getting involved in a personal work dispute, according to an official account of his crimes.

In a statement late on Saturday carried by the ruling Communist Party's anti-corruption watchdog, the Ningxia government said the fire exposed a lack of concern and lack of sense of responsibility by certain officials.

Warnings that Ma could carry out an extreme act were ignored, and steps were not taken to prevent him starting the fire, it said.

Two of the 11 officials punished for dereliction have already been handed over to authorities for prosecution, including a senior Yinchuan police officer, while others have been given administrative punishments, the government said.

Bus fires are not uncommon in China, where regulators have blamed some recent blazes on flawed design. In 2013, a bus fire blamed on a suicidal man killed 47 in the coastal city of Xiamen.