PESHAWAR, Pakistan: A suicide bomber killed 13 people and injured 23 in northwest Pakistan Monday, in an attack which the Taliban described as revenge for the hanging of a militant assassin last week.

The bomber, whom police said was aged around 20 and had up to six kilograms (13 pounds) of explosives strapped to his chest, attacked as lawyers and litigants were arriving at a court complex during the morning rush hour in the town of Shabqadar.

Senior police official Fayaz Khan said 13 people were killed and 23 wounded after the bomber blew himself up inside the complex, with the toll confirmed by a local administration official.

Schoolteacher Murid Khan, who was in the complex for a land dispute hearing, said he was getting documents photocopied when he heard gunshots.

“I looked back and there was a huge explosion,” he said, adding the blast threw him over the photocopier.

“I heard screams and saw black clouds of smoke, then I fell unconscious” after being hit by two pieces of shrapnel, he said.

The Pakistani Taliban’s Jamat-ul-Ahrar faction claimed responsibility for the attack, saying it avenged the hanging of Mumtaz Qadri — feted as a hero by some after he gunned down the liberal governor of Punjab in 2011 over a call to reform the country’s blasphemy law.

Qadri was hanged on Feb. 29 in what analysts described as a key moment in Pakistan’s long fight against militancy, saying it demonstrated the government’s resolve to uphold the rule of law rather than allow extremism to flourish.

His funeral brought up to 100,000 people on to the streets, hailing him as a hero.

Monday’s blast also targeted the court complex because Pakistan’s judiciary was strengthening “un-Islamic laws,” Ehsanullah Ehsan, a spokesman for the Taliban, told AFP.

Local TV channels showed footage of victims being rushed to hospitals soon after the blast.

Authorities said two children and two policemen were among the dead. Senior regional police official Saeed Wazir praised the bravery of officers who “sacrificed their lives.”