Property dealer Dheeraj, 37, was killed while his father Jagvir, 65, was injured in indiscriminate firing at their office in Sadarpur village on June 26.
Initially, the police suspected that the duo were attacked over some financial dispute, however, it has now emerged that Dheeraj was murdered by his maternal cousin Varun and his two accomplices, said Superintendent of Police (city) Salman Taj Patil.
"The firing was captured by CCTV camera in the deceased's office. During checking near ALT trisection, police nabbed Varun and recovered two 9mm pistols and a bike from him," said Mr Patil.
"During interrogation, Varun admitted that he had illicit relations with the deceased's wife, Preeti. The husband and wife had heated arguments many times over the issue. Varun and Preeti conspired to kill Dheeraj, grab his property and then marry each other," said Mr Patil.
Varun hired the killers luring them with the promise to give half share in the property.
The other two assailants, Jaideep Sirohi and Monu are still at large and are being pursued by the police. The police have arrested Preeti as co-conspirator in her husband's murder.
Meanwhile, the suspects in the case - Naresh, Beekar and Babbal - who were named by Dheeraj's uncle, have been given clean chit.
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