Police said property dealer Rajeev of Greater Kailash area in south Delhi was returning home from office on Saturday night when he fatally hit Kundan Yadav, 25, with his Audi car on Bahadur Shah Zafar Marg, just 100 metres from the Delhi Police headquarters.
"During preliminary investigation, we found Rajeev was driving the white Audi and instead of stopping to help an injured Kundan Yadav, he sped away. After the accident, he gave his car to a service station," Deputy Commissioner of Police Mandeep Singh Randhawa said.
He said police is interrogating Rajeev to ascertain his involvement in the crime and whether he was inebriated at that point in time.
Police traced Rajeev after his car's registration number showed up in closed-circuit television footage.
Bihar native Kundan Yadav, who worked at a juice shop, was crossing the road around 11 pm on Saturday when he was fatally hit.
Eyewitnesses said Mr Yadav was writhing in pain and shouting for help but police reached the spot only after 15 minutes.
Mr Yadav had been feeding the poor people sleeping on roadsides in the ITO area for the last couple of years.