"The build-up to violence started on Monday morning. Phones that have been seized revealed that proper mobilisation was being done. Chats include for stones to be brought at Maujpur, Babarpur, Chand Bagh and Kardampuri. Moreover, hate speeches, rumour-mongering and plan for attacks were discussed," sources said.
"Apart from locals, police has found outsiders, from neighbouring Uttar Pradesh, came in numbers and participated in the violence. Only on Tuesday evening, borders were sealed," sources added.
Sharing details regarding the use of weapons, sources informed that rounds were exchanged on Monday and Tuesday. They said that not only police came under attack from heavy stone-pelting, but protestors also used country-made revolvers in several places.
Intelligence Bureau Officer Ankit Sharma's body was also recovered from the Chand Bagh area here on Wednesday.
Delhi Police has formed a special team to probe Sharma's murder case. "He was beaten and tortured. Before dumping him in a drain, a stone was used to beat him," sources said.
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"Apart from rioting, looting and robbery took place at several places and involvement of local gangs is being looked into," sources further said.
At least 28 people, including a police head constable, have died, while around 200 people have sustained injuries in the violence that raged for three days in North-East Delhi. Properties worth crores of rupees have been damaged in the arson.