In a rare targeted attack on an IB official, deputy director Qamar Raza was shot dead in the Liaquatabad area, they said.
According to details, unidentified assailants on a motorcycle fired on the officer, when he was going towards his house after parking his car, fatally wounding him.
Earlier in July, a Crime Investigation Department (CID) officer was shot dead.
CID sub-inspector Ghufran Amin was shot dead near his house in Pathan Colony.
He was the third CID officer to have been killed in a month.
The police said that Amin's murder was part of an ongoing series of revenge killings of police officers taking action against target killers and extortionists.