A blast at the accident and emergency department of a hospital in Pakistan's Quetta, where several lawyers were gathering to support a slain colleague, has wounded several.

There were reports of several people killed in the explosion, but the death toll was unclear, according to an Al Jazeera reporter in Pakistan, who said the attack was a "suicide blast".

The group of lawyers were at the unit because earlier in the day armed men had shot Bilal Anwar Kasi dead, reports said.

Several people were wounded as they rushed to leave the hospital, the Dawn newspaper reported.