Four policemen, including a senior officer, were killed after members of the banned Tehrik-e Taliban Pakistan (TTP)* detonated a roadside bomb on their vehicle in northwest Pakistan on Thursday, authorities said.
Six other policemen were wounded when fighters of the proscribed terror group, also called Pakistani Taliban, targeted a police station in the same area.
Ashfaq Khan, a local police officer, confirmed to reporters that security forces were carrying out a search to find those responsible for the deadly attack.
Pakistan Prime Minister Shehbaz Sharif said that he was "saddened" by the loss of lives of policemen in the attack.
"Heart saddened by the martyrdom of 4 police personnel including DSP as a result of a militant attack in Lakki Marwat. The sacrifices of our police officers in the war against terrorism are unforgettable," he tweeted.
Subsequently, the TTP claimed responsibility for the attacks, claiming they were carried out in retaliation for the killing of its members in operations led by one of the officers, Iqbal Mohmand, slain on Thursday.
Since it unilaterally ended its ceasefire with the federal government, the TTP has escalated its attacks on Pakistani security forces and state institutions.
Among the deadliest militant attacks witnessed by Pakistan in recent years was the suicide bombing of a Peshawar mosque in January, which left more than 100, including dozens of policemen dead.
The Pakistani authorities alleged that the TTP was behind the attack.
Last week, a senior army officer Brigadier Mustafa Kamal Barki died in an exchange of fire with militants in South Waziristan.
* a terror outfit banned in Russia and other states