The BBC's Dumeetha Luthra is standing on the roof of the governor's office in Basra, which has been occupied by Iraqis loyal to a radical Shia Muslim cleric.
The Basra sit-in remains peaceful
She said dozens of armed militiamen had entered and said they were going to stay there peacefully until Sheikh Yakubi, the deputy of young radical Shia cleric Moqtada Sadr, was released from US custody.
"There are certainly a lot of guns around - but I haven't seen any of them being fired yet," Luthra added.
"I haven't seen a British presence here at all," she said.
British troops had been allowing the Iraqi police to deal with recent demonstrators in Basra - but many officers who supported Mr Sadr's group were now working with the militia to occupy the building, Luthra added.
"What I'm seeing here on the roof at the moment is people in uniform sitting around with their guns chatting to the militia."
The Shia cleric had always been against the US coalition and told his followers not to work with them, Luthra said.
"He is a young firebrand and there has been a lot of talk of young people following him.
"Recent incidents have ratcheted up the tension and perhaps pushed more support towards him."
The BBC's Barbara Plett is outside Mr Sadr's offices in the Sadr City area of Baghdad.
"There is quite a large crowd gathered - they are chanting and punching the air with their fists and waving flags.
"I have seen at least two funeral processions so far, and just down the road there is some black smoke rising - it looks like people are burning tyres.
Sadr City had seen some of the fiercest fighting in Iraq on Sunday night, Plett added.
"Seven American soldiers were killed and a large number of Iraqis too, we're told.
"American forces say they moved in when Sadr's supporters tried to take over government buildings and police stations.
"They are still here in force outside the local government building - I've counted, at one time, nine military vehicles including four tanks, and there are soldiers standing in front of the building.
"The US military says it has restored security here - although it might be a more accurate description to say it has pacified the area at least for now."