Pakistan Anti-PM Protesters Storm State TV

Hundreds of protesters trying to topple Pakistan's government briefly seized the state broadcaster on Monday, intensifying a fortnight-long political crisis that has shaken the nuclear-armed nation.

Transmissions of the main Pakistani Television (PTV) news channel were cut after protesters armed with clubs stormed the building in Islamabad's high-security "red zone", before being removed by security forces after around half an hour.

The occupation came after fresh street clashes between riot police and followers of opposition politician Imran Khan and populist cleric Tahir-ul-Qadri, in which officers were pelted with rocks and responded with teargas.

Beleaguered Prime Minister Nawaz Sharif held talks with the powerful army chief and opposition leaders in a bid to find a way out of the crisis, which has weakened his hold on power.

Khan and Qadri supporters have been protesting in the capital since August 15 to try to oust Sharif over alleged election fraud, triggering a crisis that has raised the spectre of military intervention in a country ruled for half its history by the army.

Late on Sunday the powerful army called for a peaceful settlement, but warned it was "committed to playing its part in ensuring security of the state" after weekend clashes left three dead and hundreds injured.

A senior figure in Khan's Pakistan Tehreek-e-Insaaf (PTI) party on Monday dramatically claimed the protests were being orchestrated by the military, echoing concerns voiced by analysts and government officials.

The crisis escalated on Saturday night when, after two weeks of charged but peaceful protests, violence erupted as followers of PTI and Qadri's Pakistan Awami Tehreek (PAT) tried to storm Sharif's official residence.

After an emergency meeting of top brass in the garrison city of Rawalpindi on Sunday the army voiced support for democracy -- but also stressed its own role in maintaining security.

The protest leaders claim that the 2013 general election which swept Sharif to power was rigged, even though local and foreign observers rated the polls as relatively fair and credible.

On Monday the PTI president Javed Hashmi -- who publicly fell out with the party on Sunday -- claimed Khan had said a plan was in place.

"Our leader told us that the matters have been settled and elections will take place in September," he told reporters.

"Imran Khan said we can't move ahead without (the) army."

Sharif aides have made similar remarks but this is the first time a senior figure from the protest movement has aired such claims.

PTI spokeswoman Shireen Mazari said Hashmi's allegations were "unfounded".

"The fact is that there was no such talk in any meeting nor is there any such covert agenda," she said in a statement.

Monday's clashes began in the morning when more than 3,000 demonstrators tried to march once again on the residence as heavy rain fell on Islamabad, an AFP journalist at the scene said.

Protesters pelted riot police with stones and some smashed up motorbikes with wooden clubs. Police tried to respond with tear gas but the rain appeared to render it ineffective.

Some managed to breach the perimeter fences of some official buildings, but paramilitary security forces stopped them at the entrance to the premier's house. There were further scuffles late in the afternoon.

Meanwhile, an AFP reporter saw more than 300 protesters, many armed with wooden clubs, enter the PTV building around 11:00 am (0600 GMT) shouting anti-government slogans.

Television footage showed some of them beating a photo of Sharif with sticks and spitting on it.

Army and paramilitary forces cleared the building without violence -- they were even cheered and applauded by the protesters as they left.

Both Khan and Qadri initially tried to distance themselves from the incident, saying their activists were not involved.

But several were wearing PTI scarves and t-shirts and Khan later apologized, saying his party workers had "become emotional".

PTV managing director Mohammed Malick told AFP the protesters had "ransacked" the building.

"They destroyed equipment and stole equipment. No one seriously injured but we're pretty shaken up," he said.

The protest leaders have drawn thousands to the streets of Islamabad, but their call has not mobilized mass support in a country of 180 million people.

Political analyst Mosharraf Zaidi dismissed the idea that either protest movement was serious about changing the country -- and gave a gloomy forecast for Sharif.

"This is not about reforms, this is simply about removing the prime minister from his seat as prime minister and I think that eventually they are going to succeed in doing that," Zaidi told AFP.