Acting on a tip-off, police arrested Vishal alias Bunty (19), Jai Chand (21) and Mahesh Gupta (21) and detained the four juvenile offenders.
Six pistols and 28 live cartridges were seized from them.
"On a tip-off, a trap was laid to arrest Vishal alias Bunty who was wanted in five cases including murders. At about 7:00 PM, Vishal along with six other associates reached Dakshinpuri area. When a police team challenged them, Vishal opened fire on them. However, after a short struggle the police team managed to apprehend all the seven persons," DCP (South-East) P Karunakaran said.