The public were denied access to a council meeting after a pro-Palestine protest amid "disruption" fears.
Dozens of Pro-Palestine supporters gathered around the Camden Town Hall holding banners and chanting ahead of a meeting on Monday (March 4).
The vote to decide council tax was among items on the agenda - and this was given as a reason for the exclusion.
A smaller number had gathered outside last month's meeting and once inside mounted an orchestrated protest that halted proceedings for 30 minutes.
Addressing the chamber, Camden mayor Cllr Nazma Rahman said: "As members are aware and under the advice I took the extremely rare step of excluding the public from the chamber before the meeting began."
Explaining the decision, borough solicitor Andrew Maughan said allowing people in the gallery would "disrupt" the meeting.
He added a number of factors contributed to the decision, including the last meeting where "an organised group individually one by one disrupted the meeting".
He said this technique was "common around London and applauded" and one he was under "no doubt" they would repeat it.
"Something was thrown into the last meeting, no-one was hurt but someone could have been hurt," he added.
They said officers had been monitoring social media, where the language was getting increasingly "aggressive".
He said "on the balance of probabilities" officers had decided to exclude the public from the meeting.
Another reason for excluding the public was that the meeting was held to set the council tax increase, which had to be done by March 11.
Mr Maughan said with people in the gallery "it would be difficult to enable members to make their points".
Following the meeting, one of the activists, who gave her name as Hannah, said: "It is absolutely wrong that the council is allowed to sit without having people in the public gallery.
"This has never happened before. People have always been in whether it's about closure of nurseries, closure of libraries, people go in the public gallery to hear the council who are a body that represents us and tonight when we wanted to make a statement and challenge the council and Labour's position not calling a ceasefire, suddenly the gallery is closed.
"This is unusual, anti-democratic and all the people on the demonstration were extremely upset because the council should be accountable to the people."
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