Several people were killed in an explosion and fire at a gas filling station in Nasarawa state, central Nigeria, the government said on Monday. 

There was no immediate confirmation of the death toll after the blast at the plant in the state capital Lafia but dozens of people were also said to have suffered burns. 

Television pictures showed firefighters dousing vehicles on the road after the blast, which is said to have happened as gas cylinders were being refilled. 

Danjuma Bisalla, deputy head of the Nasarawa state fire prevention department, said traders alerted them to a gas leak but they were unable to stop the fumes igniting. 

One onlooker told the private Channels TV that most of the injured were onlookers who refused to move. 

President Muhammadu Buhari had offered his condolences to those killed, his spokesman Garba Shehu said in a statement, adding that "several" people were killed.