DHAKA: Protesters took to the streets across Bangladesh Tuesday to demand the death penalty for the killers of a 13-year-old boy as anger mounted over the sickening lynching which was captured on video and then went viral.

Bangladeshi police have now arrested five people over the July 8 killing of Samiul Alam Rajon, who was tied to a pole and then subjected to a brutal assault in which he pleaded for his life.

One of those arrested was detained in Middle East after outraged members of the large Bangladeshi expat community there shopped him to police.

The 28-minute video of Samiul, which was widely circulated after being posted on social media, has prompted deep soul-searching among Bangladeshis as well as a series of mass protests.

Nearly 2,000 people demonstrated in a downtown plaza and at the scene of the murder in Samiul's home city of Sylhet on Tuesday demanding that the killers be sent to the gallows.

"There were around 1,500 people in the main protest. The protesters were peaceful and they demanded public execution of the killers," local police chief Akhter Hossain told AFP.

Samiul's father, a van driver, passed out at the protest and was rushed to a hospital, local media said. Protests were also held in the capital Dhaka where hundreds shouted "Hang them, hang them" as they massed outside the national press club, an AFP photographer at the scene said.

There were also protests in nearly a dozen other cities and towns across the country where protesters held placards and banners calling for immediate arrest of the killers and their quick trial.

Although executions are rare in Bangladesh, several Islamist leaders have been hanged in recent months over their role in the 1971 independence war.

Thousands of demonstrators held similar protests on Monday, venting their anger at police for not doing enough to hunt down the killers.

Samiul was accused by his attackers of stealing a bicycle although his family insist that the youngster was innocent.

Police said officers had arrested three people overnight, including the wife of one of the suspects and two men who were at the scene.