After nearly 12 hours of anti-terror operation, a suspected terrorist believed to be influenced by Islamic State of Iraq (ISIS) and having possible links to the Bhopal-Ujjain train blast was killed early Wednesday in Lucknow.

"After opening the doors of the house (where the terrorist was holed up), the force went inside and found the suspect dead along with weapons," Additional Director General of Police (Law and Order) Daljit Chaudhary said.

"The operation stands closed now. Rest of the legal formalities will subsequently take place," he added.

Inspector General (IG) of Anti-Terrorism Squad Aseem Arun revealed the terrorist identified as Saifullah was an active member of ISIS.

"The slain terror suspect belongs to the Khurasan module of the ISIS and was an active member. But, whether he has been indoctrinated or not is a matter of investigation," Arun said.

"Efforts were made to catch the suspected terrorist (identified as Saifullah) alive, but unfortunately this did not materialise. We fired tear gas shells and chilly bombs, so that he comes out. But, he did not come out," he added.

"One pistol, revolver, knife and ammunition have been recovered," he said

Saifullah, was linked to the Bhopal-Ujjain train blast in Madhya Pradesh on Tuesday that injured ten passengers.