Additional Inspector General (AIG) Telecommunications Hamid Shakeel and two other police officials were martyred in a suicide attack on Thursday morning in Quetta, according to police officials.
Four others have been injured, police and hospital sources told DawnNews.
The blast targeted senior police official Hamid Shakeel who was leaving his residence and was passing near Chaman Housing Scheme at the time, police said.
Senior Superintendent Police Naseebullah told DawnNews that the blast was a suicide attack.
The injured have been admitted to Civil Hospital Quetta for treatment, where emergency has been imposed.
Sources told DawnNews that the AIG's car was badly damaged in the explosion.
The area has been cordoned off and a search operation is underway in the surrounding areas.
Born in 1960, Hamid Shakil has previously served as deputy inspector general operations, acting DIG investigations, and AIG operations, as well as holding a number of other posts throughout his career with the Balochistan police.
Balochistan Governor Muhammad Khan Achakzai and Chief Minister (CM) Sanaullah Zehri strongly condemned the attack.
The government will not bow down before terrorists, the CM said, adding that the culprits behind the attack would be brought to justice.
Balochistan police in the line of fire
Police officers are said to be high-risk targets in Balochistan. After an attack on Quaidabad police superintendent Mubarak Shah Achakzai, a police official told Dawn "We expect more attacks in the near future."
Explore: Situationer: Balochistan police in the line of fire
Balochistan has been divided into two areas – A and B – based on how their security is organised.
Siddique Baloch, editor of the Balochistan Express, explained to Dawn in July that police are responsible for maintaining law and order in areas that fall under category A.
The category covers 10 per cent of the province’s area, while the remaining province (category B) is under the control of the Balochistan Levies.
"As much as 90 per cent of violent crime occurs in areas covered by police," Mr Baloch said.
The primary reason he cited is the high level of organisation in police ranks, a fact that seems to incite violence against it by terrorist outfits.
Around 2001, at the onset of the deterioration in Balochistan’s security situation, Baloch separatists would target police constables in Quetta, mainly because most cops hailed from Punjab.
With the passage of time, as the ethnic composition of the police department changed, sectarian and militant outfits began carrying out attacks against cops. In recent years, most targeted attacks against policemen have been claimed by the Lashkar-e-Jhangvi (LeJ) or the TTP.
According to security analysts, military operations in the Federally Administered Tribal Areas (FATA) pushed militants towards the northern Pakhtun belt of the province. They have managed to regroup there and collaborate with sectarian outfits to target state installations and security forces.
Journalist Shahzada Zulfiqar had said in July that the recent attacks on police officers suggest that militants are still capable of carrying out attacks in Quetta and elsewhere in the province.
"It is their (militants’) strategy to target police or other law enforcers, remain in hiding, change their position, and move here and there. This is just to show that they exist and are still powerful."
According to the police department, it has lost as many as 834 officers and constables in different incidents since 1979.
Additional reporting by Hafeezullah Sherani.