New Delhi: A Jaish-e-Mohammed Sajjad Khan, a close aide of Pulwama attack mastermind Muddasir was arrested here, police said on Friday.

Sajjad Khan (27), a resident of Pulwama, was arrested near the Lajpat Rai market late Thursday night, they said.

"Muddasir, the mastermind of Pulwama attack was killed in an exchange of fire with security forces in Jammu and Kashmir recently," Pramod Singh Kushwah, Deputy Commisisoner of Police (Special Cell) said.

Sajjad was tasked by Mudassir to establish a sleeper cell in Delhi, the officer added.

Forty Central Reserve Police Force (CRPF) personnel were killed in Jammu and Kashmir's Pulwama district after a JeM terrorist rammed an explosive-laden vehicle into their bus, which was part of a convoy going to Srinagar from Jammu in February.