The accused have been identified as Rakesh Sirohi, Udishter Sharma, Vikas Tomar, Sunil, Kamal, Rahul and Malik, they said.
They were arrested from Aradhana Crossing in Sahibabad area this afternoon.
"Police got information that all seven accused were coming towards Aradhana Crossing. A trap was laid and they were arrested. They have confessed to their crime," said a police official.
The official claimed a pistol and two live cartridges were seized from the accused.
Businessman Alekh Garg, a resident of Nehru Nagar, was fired upon when he was going to his house in his SUV car on March 17, according to police.
After the firing, the attackers had fled the spot.
Locals informed the police, which later rushed Garg to a nearby hospital.