Last night In Brighton city centre, around 2000 people gathered - some holding banners, saying things like "stand up to racism" and "refugees are welcome here."
Reports emerged of protesters wanting to target an immigration lawyer in the city.
Eight anti-immigration protesters were corralled by police against the BBC building for their safety.
In Portsmouth, police redirected anti-immigration protesters away from the main thoroughfare in and out of the city.
There were also protests in Southampton.
Around 400 individuals gathered at Cambridge Gardens in Hastings for a peaceful demonstration overseen by police without any significant incidents or arrests.
Sussex Assistant Chief Constable Paul Court said: “We would like to thank communities for their support, engagement and providing information to help us keep communities safe.
“There will be a continued police presence and additional policing resources in coming days to maintain peace and prevent disorder.
"We would like to thank the community for their support, engagement and providing information to help us keep people safe.
“The message remains the same. Anyone planning to take part in criminal disorder in Sussex will regret their actions. Do not do it. Our officers are mobilised and fully prepared, and the ramifications for those involved will stretch far beyond the conclusion of any incidents.
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