India’s anti-terror investigating agency said on Sunday it arrested a man from Indian-controlled Kashmir on suspicion of conspiring with a suicide bomber to carry out a deadly car blast in the capital New Delhi.

The National Investigating Agency said in a statement that the car that exploded on Monday was registered to Amir Rashid Ali, who it alleged had travelled to New Delhi from Indian-controlled Kashmir to buy the car. It said Ali’s arrest was a “major breakthrough” in the case.

The explosion killed 10 people and injured 32 others near the city’s historic Red Fort. Indian officials called it a “heinous terror incident” carried out by “antinational forces”.

The car blast happened hours after police in Kashmir said they had dismantled a suspected militant cell operating from the disputed region, arresting at least seven people, including two Kashmiri doctors from Indian cities, and seizing a large quantity of bomb-making material.

The investigating agency identified the car’s driver and suspected suicide bomber as Umar Un Nabi, also a Kashmiri, a doctor teaching at a medical college in the city of Faridabad, near New Delhi.

Government forces blew up his family home in the southern district of Pulwama on Thursday night, officials said, as a reprisal for the attack.