DHAKA • Eight people have been killed in vigilante lynchings in Bangladesh sparked by rumours on social media of children kidnapped and sacrificed as offerings for the construction of a mega bridge, police said yesterday.

The victims, including two women, were targeted by angry mobs over the rumours - spread mostly on Facebook - that said human heads were required for the massive US$3 billion (S$4.1 billion) project, police chief Javed Patwary said.

"We have analysed every single case of these eight killings. (Of) those who were killed by lynching mobs, no one was a child kidnapper," Mr Patwary told reporters in Dhaka.

More than 30 other people have been attacked in connection with the rumours.

Mr Patwary said police stations across the country had been ordered to crack down on the rumours, and at least 25 YouTube channels, 60 Facebook pages and 10 websites have been shut down.

However, several posts that shared the rumour were still up on Facebook yesterday.

Local media said the lynchings started after reports circulated of a young man allegedly found carrying the severed head of a child in the northern district of Netrokona.

Among the latest victims was a single mother of two, Ms Taslima Begum, who was beaten to death in front of a Dhaka school last Saturday by a mob which suspected her of being a child kidnapper, a police official said.

A deaf man was also beaten to death outside the capital that day while trying to visit his daughter.

Police said eight people have been arrested over Ms Begum's murder, and at least five others detained for their role in spreading the rumour on social media.

Police are so concerned about the deadly fallout in rural towns that officers are trying to counter the rumour using loudspeakers.

Ansar paramilitary security forces and village guards have also been asked to warn villagers, according to media reports quoting Ansar major-general Kazi Sharif Kaikobad.

The lynchings could be "a sign of people's distrust in the existing law and order system", Dhaka University sociology professor Monirul Islam said.

The bridge - which is set to be Bangladesh's biggest - is being built on the Padma River, a major tributary of the Ganges.

Rumours of human sacrifices being required for a bridge in Bangladesh have surfaced before, with several people attacked in 2010 over another structure, according to local media.

AGENCE FRANCE-PRESSE