The death toll from a mosque collapse in eastern Pakistan has risen to 24, rescuers said after pulling more bodies from the rubble.

The worshippers were killed when the roof of the mosque collapsed in Lahore on Tuesday as around three dozen people gathered for afternoon prayers.

"The death toll from the incident is now 24. The ages of the worshippers who died are between 15 to 35 years," Mohammed Rashid, an official at the rescue control room, told the AFP news agency on Wednesday.

"We have also taken out seven seriously injured people from the rubble," he said.

The collapse happened in Daroghawala, a low-income neighbourhood in the outer city with narrow and congested streets.

District administration chief Mohammed Usman said the rescue operation would continue until all the rubble was removed.

"According to locals' claims it seems almost all people have been recovered but we will continue our efforts till the removal of the whole debris or any doubts [about people still trapped under the rubble]," Usman said.

Pakistan has a poor safety record in the construction and maintenance of buildings.

Many of the more than 200 killed in floods across Pakistan this month have been victims of collapsed roofs.