A group of Bangladeshi men have filmed a gruesome video, in which they beat to death a 13-year-old boy accused of stealing a rickshaw van, and then uploaded it on Facebook.

Police already arrested one of the alleged killers, Muhit Alam, 32, as he was trying to dump the body of Sheikh Samiul Alam Rajan after subjecting him to torture for almost half an hour, in the outskirts of Sylhet.

In the clip, the terrified boy is seen crying and pleading for his life while being tied to a pole of a shop and beaten with a stick. "We will teach you a lesson today so that you can never steal in your life again," the torturers are heard saying, according to the Dhaka Tribune.

When Rajan asks for some water, the men tell him to drink his own sweat. The alleged killers are heard laughing and mocking the boy while he screams and cries. At some point, his left hand and right leg gets wrung and the men starts hitting him in the head, stomach and nails.

"His bones are apparently intact, beat him more," one said, according to bdnews24.com.

The man holding the camera then said: "I have posted it on Facebook. The whole world will see it now."

Rajan's family alerted police after the boy did not come back home after a whole day spent selling vegetables. His father, Sheikh Azizur Rahman, told the Dhaka tribune that Rajan dropped out of school to support the family.

"My son was not a thief. He lost his life to satisfy the expatriate's desire to catch a thief. I want justice for my son; I want his killers to be arrested and punished," said Rajan's mother Lubna Akhtar.

A post-mortem examination established the boy died of a brain haemorrhage. More than 60 injuries were found on his body.

Muhit is the primary suspect in the case, which involves also his brother Kamrul Islam, 24, and their accomplices Ali Haider, 34 and guard Moyna Miah, 45. They are all charged with murder.