The Counter-Terrorism Department (CTD) of Sindh police on Sunday arrested a "most wanted" terrorist of the banned Tehreek-i-Taliban Pakistan (TTP) in Karachi, the security agency said in a statement.

The CTD and Rangers arrested the militant in a joint operation that was carried out near the Naurus Chowrangi in the SITE area.

During the raid, a man identified as Muhammad Ilyas was arrested. "Illegal weapons and ammunition were also seized from his possession," the CTD said.

"During interrogation, the suspect confessed that he, along with his accomplices, killed Sher Ahmed Khan in the SITE area in 2013."

CTD statement noted that Ilyas had joined the TTP in 2012.

"He is being interrogated in other cases as well, while further confirmations are underway from nearby police stations," the statement added.