Armoured police vehicles blocked Benazir Bhutto's car after she was allowed to leave her home in Pakistan following appeals to let her go, an AFP correspondent witnessed.
"My fight is not with you, my uniformed brothers, I am fighting for democracy," Bhutto told police through a megaphone. "I appeal to you to clear the way. Let me go through, please."
An armoured personnel carrier and a fortified police prison van moved into position to stop her car from moving any further after she was allowed through a second cordon outside her home.
Hundreds of riot police lined up behind the vehicles and called by radio for reinforcements.
Bhutto's car had moved around 600 feet from her house since she left it about two and a half hours previously in a bid to address a rally in nearby Rawalpindi against a state of emergency.
Bhutto added: "Pakistan's integrity is in danger. Militants are waving their flag, the flag of Pakistan is being lowered."
"There is no government, the chief of army staff is ruling under martial law," she said referring to military ruler Pervez Musharraf.
Bhutto 'under house arrest'
Street battles between activists of the Pakistan Peoples Party (PPP) and the police erupted on Friday as the party's supporters tried to reach the venue of a rally where the former premier was scheduled to make a speech. She was placed under house arrest instead.
Groups of PPP activists were playing hide and seek with the police in capital Islamabad and twin-city Rawalpindi while their party chief was put under house arrest, though the government denied it.
"It is wrong to say that she is under house arrest. Security has been provided to her," Junior Minister for Information Tariq Azeem said.
Azeem said Bhutto was free to go anywhere she liked but "the government wants to ensure her security".
Contrary to the minister's claim, heavy police deployment was seen outside Bhutto's residence in Islamabad and journalists were kept away. Even party officials were not allowed into the house.
Meanwhile, PPP workers in small groups were playing hide and seek with the police near Liaqat Bagh, the venue of the proposed rally. Carrying party flags and Bhutto portraits, they were seen marching down roads, throwing stones at policemen and running back into the narrow lanes of downtown Rawalpindi.
PPP leaders said that more than 50,000 workers have reached Rawalpindi from Lahore and other cities while thousands of them have been stopped along the way.
"We have been ordered not to allow Benazir to leave her house," a police official posted outside her residence said, adding that she has been served with arrest warrants and her house has been termed a sub-jail.
Azeem said that the security arrangements have been made on PPP's request due to the Karachi blasts on Bhutto's motorcade.
Azeem said the government would not permit any party or leader to hold a rally. He said that the law was equally applicable to all and any one violating it would be prosecuted.
About 150 people were killed and hundreds were injured after suicide bombers attacked Bhutto's homecoming rally on Oct 18. "In this situation it is important that Bhutto be provided security," Azeem said.
Benazir's spokesperson Sherry Rehman said that no detention order had been served on the PPP leader but "it's virtual house arrest". She said that more than 5,000 PPP workers have been detained in different parts of the country.
Rehman said that a large number of people were coming to Rawalpindi from Lahore and other parts of Punjab but were stopped at different points.
"Whoever tries to show up for the meeting will be arrested," said city police chief Saud Aziz.
The Liaqat Bagh ground, where Bhutto had planned to address the protest rally, was flooded with water late on Thursday night. Heavy containers and barbed wire barriers blocked the roads leading to the venue.
The police also barricaded all highways between Punjab and North West Frontier Province (NWFP) to foil the attempt of PPP workers to reach Liaqat Bagh.