Police say 140 people have been arrested after a spate of deadly mob attacks on suspected "vampires" in Malawi.

There have been at least nine killings, including an epileptic man who was burned to death and another person who was stoned to death in the country's second-biggest city, Blantyre.

The assaults started last month when rumours spread of "bloodsuckers" on the loose - and police say the situation has spun out of control.

Mobs have been putting up illegal road blocks, leading to security concerns in the southern African country.

Some residents - including health officials, teachers and traditional leaders - say their homes have been destroyed following speculation they were looking after "vampires".


Image: Malawi's President Peter Mutharika has appealed for calm

President Peter Mutharika has appealed for calm in the four districts where the attacks have taken place, saying "my government will offer protection from these alleged bloodsuckers".

Some areas have been declared dangerous zones for people working for the United Nations and US embassy.

A UN safety report on the Phalombe and Mulanje areas said: "These districts have severely been affected by the ongoing stories of bloodsucking and possible existence of vampires."

Belief in witchcraft is widespread in rural Malawi, one of the world's poorest nations, where many aid agencies work.

Police chief Lexon Kachama said: "The biggest challenge is that thieves and robbers have now taken advantage of the situation and are mounting illegal roadblocks at night in order to harass people."