Hundreds of protesters trying to topple Pakistan's government stormed the state broadcaster on Monday, intensifying the political crisis gripping the nuclear-armed nation.
Transmissions of the main Pakistani Television (PTV) news channel were cut for around half an hour before security forces cleared demonstrators from the building in Islamabad's high-security "red zone".
The brief seizing of PTV by protesters armed with clubs came after fresh street clashes in which police were pelted with rocks and responded with teargas.
Late on Sunday the powerful army called for a peaceful settlement of the political crisis that has shaken Pakistan and weakened the government of Prime Minister Nawaz Sharif.
Opposition groups marched to the capital on 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.
The military urged the government and protesters to settle their differences peacefully, but warned it was "committed to playing its part in ensuring security of the state" after clashes left three dead and hundreds injured.
Violence began on Saturday night when followers of opposition party leader and former cricketer Imran Khan and of populist cleric Tahir-ul-Qadri tried to storm Sharif's official residence.
Fresh clashes erupted on Monday morning as heavy rain fell on the capital, when more than 3,000 demonstrators again tried to march on the building, 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 heavy rain appeared to make it ineffective.
Some managed to breach the perimeter fences of some official buildings, but paramilitary security forces stopped them at the entrance to the PM's house.
Both Khan and Qadri appeared on the shipping containers they have used as stages to urge their supporters not to resort to violence.
An AFP reporter saw more than 300 protesters, many armed with wooden clubs, enter the PTV building shouting anti-government slogans.
Television footage showed some of them beating a photo of Sharif with sticks and spitting on it.
After the PTV building was cleared and transmission restarted, both Khan and Qadri tried to distance themselves from the incident, saying their activists were not involved.
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.
"While reaffirming support to democracy, the conference reviewed with serious concern, the existing political crisis and the violent turn it has taken, resulting in large scale injuries and loss of lives," the military said in a statement.
"It was once again reiterated that the situation should be resolved politically without wasting any time and without recourse to violent means."
They added: "(The) army remains committed to playing its part in ensuring security of the state and will never fall short of meeting national aspirations."
The statement opened with backing for the government but ended on a hawkish note -- which a senior government official said reflected differing views within the army's top brass.
Pakistan's last period of military rule ended in 2008. But the official said another coup remained "less likely".
"We have travelled this road for seven to eight years, so things have been tested -- the institutions are much stronger," he said on condition of anonymity.
"I hope and pray the system survives. There will be some losses but they will be recovered," he added, referring to the significant concessions that observers say the government will need to make to the army if it is to survive.
The protest leaders claim that the 2013 general election which swept Sharif to power