QUETTA, Pakistan— A suicide bomber killed at least 64 people and wounded dozens in an attack that struck a gathering of Pakistani lawyers on the grounds of a government-run hospital in the southwestern city of Quetta on Monday, police and doctors said.

Witnesses described horrifying scenes of bodies being scattered about and the wounded screaming out and crying for help. No group immediately claimed responsibility for the blast but the government said it will trace and arrest those who orchestrated the attack.

Nearly 100 lawyers had come to the hospital in the heart of Quetta, the capital of Baluchistan province, after the body of their colleague, prominent attorney Bilal Kasi was brought there.

Kasi, the chief of the province’s bar association, 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. Kasi was among the most outspoken lawyers in the province and was popular for campaigning for improvements in the lawyers’ community.

“It was a suicide attack,” said Zahoor Ahmed Afridi, a senior police officer. Afridi said the attacker hit shortly after Kasi’s body was brought in and that it seemed the two events were connected.

Abdul Rehman, the director at the Civil Hospital, said the bombing killed 64 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.

One of the survivors described a horrifying scene, saying there were “bodies everywhere.” Waliur Rehman said he was taking his ailing father to the emergency ward when the explosion shook the building.

The blast was so powerful that they both fell down, he said.

When he looked up, Rehman said he saw bodies of the dead and the wounding crying out for help. He was about 200 meters (yards) away from where the bombing struck, he added.

Another witness, lawyer Abdul Latif, said he arrived at the hospital to express his grief over Kasi’s killing. But he said he didn’t know he would “see the bodies of dozens of other lawyers” killed and wounded shortly after arriving.