A petroleum tanker truck has exploded in southeastern Nigeria, killing at least 14 people and injuring five others, an official says.

Nigeria Road Safety Commission (FRSC) spokesman Ben Ekenna said that 12 bodies were badly burned in the explosion in Anambra state on Friday.

The truck leaked into a deep pothole which then attracted heat from the exhaust pipes of nearby cars and set off the blast, he added.

Ekenna admitted local roads were in a bad state and warned that "if something isn't done quickly, tragedies like this will happen again."

Accidents on Nigeria's poorly maintained inter-city roads are common, with trucks habitually driving at breakneck speeds.

The federal road safety body, FRSC, says that around 400 people are killed every month by road accidents in the country of 140 million people.