Boxer Sumit Dahiya and his cousin Aman, 20, were arrested from Hotel Primero in Gurgaon during a raid in the intervening night of July 23-24 by the Crime Branch of Delhi Police.
"Sumit is pursuing B.A. third year from Delhi University's Rajdhani college. He is a national level boxer. He had won thrice the gold prize in All India Boxing championship played in 2011, 2012 and 2013," Additional Commissioner of Police (Crime Branch) Ravindra Yadav told IANS.
"The accused have national level and prominent Olympians in their family," the officer added.
The boxer was arrested during Delhi Police searches in west Delhi's Palam and Gurgaon for the associates of Amit Dahiya, who was killed July 22 during a shootout at Sannoth village in north Delhi's Narela area, police said.
The duo live in Delhi's Pooth Khurd village with their family members, police said.
Amit Dahiya had reached the spot with associate Parveen, who is now on the run, after robbing at gunpoint a big car near Sachdeva Public School in north Delhi's Rohini, the police said.
Sumit was present in Rohini in another car along with Aman, Amit and Parveen July 22 when they planned to hijack a new, big car.
"After the carjacking, Amit and Parveen moved towards Narela's Sannoth village where the encounter took place around 3.15 p.m. However, Sumit and his cousin went to another place in their car," said Yadav.
He said when constables Baljit Singh Chahal and A.S. Bohara spotted the robbed car without number plates near Sannoth village, they challenged the occupants.
During a scuffle with the policemen, Amit opened fire and constable Baljeet Singh was hit by a bullet in his thigh, police aid.
The constables fired in retaliation, and Amit was injured, while Parveen managed to escape, police said. Amit died on way to hospital.
"Parveen hid himself at a place and called Sumit to take him away from there. Sumit and his cousin then picked up Parveen from his hideout and assisted him to escape," said the officer.
"They themselves planned to flee to Rajasthan. However, they were apprehended," the officer informed.