(CNN)Police in the northern England town of Knowsley, Merseyside, arrested three people on Friday after violence broke out during a protest outside a hotel used to house asylum seekers.
Merseyside Police said those arrested were being held "on suspicion of violent disorder and taken to police stations to be questioned."
The protest, sparked by a video filmed near the hotel, had started peacefully, police said, but the situation later became tense and projectiles were thrown at the officers.
Videos shared online Friday from the area appeared to show officers in riot gear with large shields and a police vehicle set ablaze.
The police said they were dealing with two groups of protesters after a demonstration descended into chaos outside the Suites Hotel in Ribblers Lane.
Care4Calais, a refugee charity, tweeted: "The far right have split into three groups and surrounded us at the hotel. The police don't have the capacity to cover all three groups."
Clare Moseley, founder of Care4Calais, told the UK Press Association news agency that she "was among 100 to 120 people from pro-migrant groups who went to the scene in reaction to the protest to show support for the asylum seekers."
"I'm trying to get in touch with some of the poor men in that hotel, I can only imagine how frightened they are. It was like a war zone," she told the PA on Friday.
Assistant Chief Constable Paul White of Merseyside Police said in a statement: "We will always respect the right to protest when these are peaceful, but the scenes tonight were completely unacceptable, putting those present, our officers and the wider community in danger."
"Thankfully we have not had any serious injuries reported up to this point, but for officers and police vehicles to be damaged in the course of their duty protecting the public is disgraceful," he said.
"We have arrested some of those suspects and will continue without hesitation to review all and any evidence which comes in, through CCTV, images or other information you may have," he added.