Security forces accused of pushing man off containers in Pakistan

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.

The video shows him trying to cling on to the containers before falling.

The footage was verified by matching a video of the fall posted on social media with images uploaded by Getty Images on Tuesday of the same scene.

BBC Verify has approached the Pakistani Rangers - whose officers were allegedly involved in the incident - for comment.

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.

Protesters had said they would not leave the capital until Khan - who is in prison on several criminal charges including fraud - was freed.

But as they made their way to Democracy Square on Tuesday, they were pushed back by police firing tear gas.

PTI said in a statement on Wednesday that the protests had been "temporarily suspended" due to the "government's brutality".

It said Pakistan government forces had "launched a violent assault" on peaceful protesters "firing live rounds with the intent to kill as many people as possible."

The party has claimed that several of their party workers were killed during the crackdown and appealed for an investigation.

The BBC has not yet independently verified reports of killings, although two sources at a nearby hospital confirmed to the BBC they had received four civilian bodies with gunshot wounds after Tuesday's protests.

Pakistan's information minister has said authorities resisted firing on protesters.

Earlier on Tuesday, many Khan supporters had managed to reach the city centre but were dispersed by authorities by sunset.

Local media reported a government source saying police had arrested more than 500 PTI supporters.

Islamabad had been put under lockdown, with a heavy security presence deployed in anticipation of clashes with convoys of PTI supporters.

The convoys were led by PTI leader Ali Amin Gandapur and Khan’s wife Bushra Bibi, who was released from prison in October and has since taken a more prominent role in trying to mobilise support for Khan.

Reports say Gandapur and Bushra Bibi have left Islamabad and returned to Khyber Pakhtunkhwa province, where their convoy had come from.

Protesters were reported to have responded to a “final” call from Khan, asking them to “fight till the end” until their demands are met.

Khan has been in prison for more than a year on charges he says are politically motivated.

Even from behind bars, the former cricket star has proved a powerful player in Pakistan politics. During elections in February his party, which had been banned from standing and was forced to run candidates as independents, emerged as the single largest bloc in winning votes.

However, they fell short of a majority and their rivals united to form a new government.

The PTI has called for election results to be overturned because they say the vote was rigged, a claim disputed by the government.

-BBC