A suicide bomber blew himself up in the Pakistani capital Islamabad on 11 November, the local service of Radio Liberty reported.
At least 12 people were killed and 21 others were wounded.
The Pakistan Institute of Medical Sciences Hospital in Islamabad said at least four of the wounded were in critical condition.
Pakistani Interior Minister Mohsin Naqvi said the attacker detonated explosives near a police vehicle on the grounds of a district court in the heart of Islamabad.
“Khorasan Diari, a website that tracks militant groups in Pakistan and Afghanistan, said Jamatul Ahrar, an affiliate of the Tehrik-e Taliban Pakistan (TTP), claimed responsibility for the attack.
Pakistan has consistently accused the Taliban government in neighbouring Afghanistan of sheltering and supporting the TTP.
In October, tensions escalated into intense attacks along the 2,500-kilometre-long border between the two countries. Islamabad launched airstrikes on the Afghan capital Kabul and the southern city of Kandahar for the first time since independence in 1947.
Negotiations between the two former allies have stalled, but a fragile ceasefire has been in place for weeks.
The 11 November attack came a day after a car bombing killed at least eight people and injured 19 in New Delhi, India’s capital. Analysts fear the attacks could spark new tensions between Pakistan and India, longtime nuclear-armed adversaries who often accuse each other of supporting militants and terrorist groups.
Indian Prime Minister Narendra Modi called the 10 November blast the result of a conspiracy.
“Our authorities will uncover this conspiracy,” he said during a visit to Thimphu, the capital of neighbouring Bhutan.
The blast was the first major security incident since April, when gunmen killed 26 people at the tourist spot Pahalgam in Indian-controlled Kashmir.
New Delhi then blamed the attack on militants based in Pakistan. India’s attack on suspected militant hideouts in Pakistan-controlled parts of Kashmir nearly sparked a war between the two countries in May.