Nairobi  - At least 91 people died in Kenya after a tanker truck from which they were siphoning off petrol exploded, an official said Sunday.

Rift Valley provincial commissioner Noor Hassan Noor said the accident happened Saturday evening near the town of Molo, north-west of the capital Nairobi.

The death toll was expected to rise, with some reports suggesting it could reach 130.

Hundreds of people rushed to the tanker with jerrycans to collect fuel after they heard it had crashed and was leaking.

There were conflicting reports about how the fire started.

One witness alleged the fire was started deliberately after police officers who arrived on the scene began demanding a fee to allow people to collect fuel.

"I heard someone saying that they were going to avenge the fee by starting a fire and left the scene fearing for my life," the witness told the Daily Nation. "Moments later, I heard the explosion."

Newspapers criticized the response to the explosion, saying firefighters took too long to arrive on the scene.

The tragedy came just days after a supermarket fire in the capital Nairobi claimed the lives of at least 25 people, a figure that was also expected to rise.

Authorities were also criticized for their response to that fire.

It was not the first time people looking for free fuel have been killed in Africa. Similar incidents have taken place in Nigeria, Ghana and Cameroon in recent years, causing hundreds of deaths. (dpa)