Pakistan’s security forces have been accused of pushing a man off a stack of cargo containers during Tuesday’s protests in the capital Islamabad, where crowds demanded the release of former President Imran Khan.

Khan’s party said the incident was one of several examples of police brutality at the demonstrations and has since called off the protests.

The man had been praying on top of a container when armed officers approached him and “brutally pushed him off from a height equivalent to three storeys”, Pakistan Tehreek-e-Insaf (PTI) said.

The condition of the man is unknown.

BBC Verify has confirmed that the incident took place on Tuesday at the corner of Jinnah and Attaturk avenues in Islamabad, where protesters had gathered.

Video footage showed officers – carrying riot shields with markings indicating they were affiliated with the Pakistani Rangers, a paramilitary force – approaching a man kneeling on top of the containers before pushing him over the edge.

At least six people – four security officers and two civilians – died in clashes during the protests which began on Sunday.

On Tuesday, thousands of Khan supporters marched on central Islamabad demanding that the former leader be released.