Four officers were also wounded in the incidents in the largest city Karachi and in the garrison town of Rawalpindi.
In first incident in Karachi, two men hurled a grenade at a police van.
“The police patrolling van caught fire as one policeman was killed soon after the attack and two others were wounded. The attackers fled from the scene on a motorbike,” senior police official Faisal Bashir told AFP.
Another police official said one of the wounded officers later died of his injuries.
In a separate attack in the southern port city, gunmen opened fire on two policemen.
“One policeman was killed and another wounded in this incident,” the police official, who works in headquarters, said on the condition of anonymity because he was not authorised to speak to media.
Meanwhile in Rawalpindi, which neighbours the capital Islamabad and is home to the headquarters of the country’s powerful military, one police constable was killed and two others were wounded when they were shot at by unknown people.
“Three policemen were on a routine duty in Sadiqabad area when some unknown gunmen opened fire at them. One constable has been killed while two others are injured, Raja Fayaz, a police spokesman, told AFP.
In particular Karachi, a city of 18 million people, has been plagued by sectarian, ethnic and political violence for years. -AFP