A man has been arrested in connection with a deadly car bomb attack that killed eight people and wounded 20 others in Delhi last week, authorities have said.

The National Investigation Agency (NIA) stated the car used in the attack, described by the government as a terrorist incident, was registered in the suspect's name.

The suspect, a resident of Indian-administered Kashmir, is accused of conspiring with the alleged suicide bomber. The explosion occurred near a metro station closely located to the Red Fort, one of Delhi's prominent landmarks.

The agency announced it has seized another vehicle reportedly connected to the suicide bomber for further examination, having already interrogated 73 witnesses, including those injured in the blast.

This incident marks the first explosion in the heavily guarded city since 2011.

The attack occurred on Monday evening at 18:52 local time (13:22 GMT) when a vehicle halted at a busy traffic light before exploding.

Home Minister Shah confirmed the explosion originated from a white Hyundai i20, with footage showing the remains of a charred car amidst other damaged vehicles.

Prime Minister Narendra Modi denounced the attack as a conspiracy, pledging to ensure justice for the victims and bring all involved to account.

Opposition leader Rahul Gandhi described the news as extremely heartbreaking. Police are also investigating potential links to previous arrests in Indian-administered Kashmir and a recent seizure of 2,900kg of explosives in a Delhi suburb.

The Red Fort, a site visited by thousands daily, was constructed in the 17th century and serves as a backdrop for annual Independence Day speeches by Indian prime ministers.