The Pakistani Taliban has claimed responsibility for a car bomb that killed at least one police officer and two suspects on Friday near a residential area in Islamabad.
It was the first such attack in the capital in years.
The city has largely been spared the low-level attacks carried out in Pakistan's megacities of Lahore and Karachi, and also in border areas near Afghanistan.
Senior police official Sohail Zafar Chattha said officers had been following a suspicious taxi with a male driver and a woman passenger.
“They were stopped and the long-haired man was asked to come out,” Mr Chattha told AFP.
“He came out, but quickly went back inside and pressed a button that blew up the car.”
At least three police officers and seven other people were wounded in the explosion, said officials.
Pakistan's Prime Minister Shahbaz Sharif thanked the police for their bravery.
“Police officers stopped the terrorists by sacrificing their blood and the nation salutes its brave men,” Mr Sharif said.
Extremists Tehreek-e-Taliban Pakistan — also known as the Pakistan Taliban — called off a stop-start ceasefire with the government in November and stepped up attacks on security forces.
An umbrella group of several militant factions, TTP is separate from the Afghan Taliban but has a similar hardline ideology.
Spokesman Mohammad Khalid Khurasani said one of the group's militants carried out Friday's suicide attack in Islamabad to avenge the killing of a senior TTP leader in the summer.
Abdul Wali, also known as Omar Khalid Khurasani, was killed in a roadside bombing in August in Afghanistan’s eastern province of Paktika.
His death was a heavy blow to TTP, who blamed Pakistani intelligence agents for the killing.
Friday's attack comes after Pakistani Taliban detainees overpowered their guards at a counterterrorism centre in north-western Pakistan on Sunday and took three officers hostage.
Pakistan's military said 25 detainees linked to the Pakistani Taliban were killed in a shootout on Tuesday, when special forces raided the centre in Bannu district in the Khyber Pakhtunkhwa province.
