Police in London braced for more demonstrations on Sunday as the war in Gaza continues to inflame tensions across the U.K.

British police said they arrested 365 people in central London as supporters of a recently banned pro-Palestinian group flouted the law as part of an effort to force the government to reconsider the ban.

Thousands marched through the streets of central London Saturday to protest against the ongoing war in Gaza. The protest, organised by the Palestine Solidarity Campaign, called for an end to Israel’s offensive in Gaza.