Siwan police on Friday recovered the body of Vishnu Raj, 11, also known as Rahul, who was kidnapped on Wednesday allegedly for ransom.

The abductors had allegedly demanded Rs 30 lakh for the boy's safe release.

The police said Vishnu's body was found wrapped in a gunny bag near Amrauli village under the jurisdiction of Siwan Mufassil police station around 6am on Friday. Residents who had gone to attend the call of nature noticed the bag lying in a roadside ditch.

As news of the murder spread in the district headquarters town, a number of residents assembled near Siwan hospital and disrupted traffic.

They burnt tyres in the middle of the road and set an anti-riot vehicle, Vajra, on fire when the police tried to remove the blockade.

Over a dozen people suffered injuries in the clash that erupted. The situation was brought under control after senior police officers promised to book the culprits at the earliest.

Vishnu, residents said, was kidnapped on Wednesday evening when he was going to his family's garments shop located at Shradha Nand market in Siwan town.

The family started a search for Vishnu, a student of Class VI in a local public school, when he didn't reach the shop.

Vishnu's father Raj Kumar, a resident of Naya Bazaar in Siwan, reported the incident to the Siwan Town police station and lodged a missing-person case. On Wednesday night, he received a call on his mobile phone. The caller, who claimed Vishnu was in his custody, demanded Rs 30 lakh as ransom for the boy's release.

Raj Kumar immediately informed the police about the ransom call. The police, however, didn't take any action.

On Friday morning, Vishnu's body was recovered from Amrauli village on the outskirts of Siwan town, around 145km northwest of Patna.

A close relative said the kidnappers had made ransom calls twice (Wednesday and Thursday), and the police had directed the family not to disclose it to the media.

"Neither the police arrested any kidnapper nor did they allow the family to strike a deal with the kidnappers to save the boy's life," a relative of Vishnu said.

Siwan superintendent of police (SP) Saurabh Kumar Shah said a special investigation team headed by additional superintendent of police Kartikey Sharma had been constituted to crack the case at the earliest.

"Justice will be delivered to the victim's family," Shah told The Telegraph over phone.

Last week, RJD youth wing leader Minhaj Khan was killed in Siwan, triggering protests over the police's failure to curb crime in the district.