A breakaway faction of the Taliban in Pakistan has claimed responsibility for the suicide attack at a hospital in Quetta which killed at least 64 people.

In a statement, Ahsanullah Ahsan, spokesman for Jamaat-ul-Ahrar militant group, also said their men killed Bilal Kasi, the president of Baluchistan Bar Association.

They then targeted the mourners who had gathered at the government-run Civil Hospital in the south-western city to pay their respects to Mr Kasi.

The group has been behind several acts of terrorism in Pakistan in recent years. The claim could not be independently verified.

Nearly 100 lawyers had gathered at the hospital in the heart of Quetta, the capital of Baluchistan province, after the body of Mr Kasi, a prominent local attorney, was brought there.

Mr Kasi was shot and killed by gunmen earlier on Monday as he was on his way to his office. The lawyers gathered at the Quetta Civil Hospital to express their grief as is common with public figures.

Mr Kasi was among the most outspoken lawyers in the province and was popular for campaigning for improvements in the legal community.

Abdul Rehman, the director at the Civil Hospital, later said the bombing killed 67 people, mostly lawyers. He said they were also treating 92 wounded in the explosion.

Two journalists working for Pakistani news channels were also killed in the attack, according to Shahzada Zulfiqar, the President of the Quetta Press Club.

Sanaullah Zehri, chief minister in Baluchistan province, said both the bombing and Mr Kasi's slaying seemed to be part of a plot to disrupt peace in the provincial capital.

Sarfraz Bugti, the provincial interior minister, denounced the attack as an "act of terrorism".

Prime Minister Nawaz Sharif strongly condemned the blast and expressed his "deep grief and anguish over the loss of precious human lives".

"No one will be allowed to disturb the peace in the province that has been restored thanks to the countless sacrifices by the security forces, police and the people of Baluchistan," he said in a statement.

Later on Monday, the prime minister traveled to Quetta to meet the wounded and assess the situation.