The police said that eight teams are working to crack the case. They are probing other angles including personal enmity and professional rivalry, a senior police officer said today.
The police called a few men for questioning and inquiry but no headway had been made so far. It is suspected that the accused were students of School of Open Learning, Delhi University.
Delhi Police spokesperson Dependra Pathak said that the Crime Branch has been brought in to assist the district police in its probe in the case.
The Crime Branch team visited the spot and questioned some eyewitnesses.
Ravinder (32) was beaten to death allegedly by a dozen men after he objected to two of them urinating in public near the metro station on Saturday.
The police have collected CCTV footage from the liquor shop in which two of the accused can be seen. They are trying to ascertain their identity.
Yesterday, Prime Minister Narendra Modi had condemned the killing and directed the authorities to punish the culprits.
Urban Development Minister M Venkaiah Naidu, accompanied by Delhi BJP president Manoj Tiwari, met the family members of the victim yesterday.
The Delhi government has announced Rs 5 lakh compensation for Ravinder's family.
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