Police forces across the country are bracing for the possibility of protests in response to the suspected beheading attempt in Belfast last night by a Sudanese migrant.Government ministers have called for calm after hard-right politicians urged Britons to 'loudly' take to the streets nationwide this evening, with demonstrators already gathering in some areas.Disturbing footage appearing to show a man hacking at another man's neck was shared widely on social media and has been furiously politicised by some.Tommy Robinson shared a list of 70 locations in towns and cities around the UK where protests have purportedly be planned - though insisted 'these are not my protests' and that he is merely 'passing on' information.With nerves running high on all sides, Education Secretary Bridget Phillipson insisted that more violence would be the 'worst possible reponse'. She told LBC Radio: 'What we’re urging now is a period of calm.'I appreciate that people are horrified by what they have seen, but the worst possible response to that kind of violence would be further violence or disorder.'Dozens of protesters gathered outside a hotel used to house asylum seekers in Southampton ahead of the 7pm start time widely advertised.The crowd held Union and St George flags as they gathered outside Highfield House Hotel.Organisers of the 'flash protest' said it was in response to the 'disgusting video we are witnessing', in what is understood to be a reference to the stabbing in Belfast on Monday. Police forces across the country are bracing for potential protests in response to the suspected attempted beheading in Belfast last night Dozens of demonstators were gathered in Southampton before 7pm outside a hotel used to house migrants A man, aged in his 30s, has been arrested on suspicion of attempted murder following the 'brutal' assault on Monday nightLabour ministers have been under pressure to provide 'full transparency' about how a Sudanese man, who was this evening charged over the attack.The suspect, 30, was arrested on suspicion of attempted murder on Monday night and charged on Tuesday evening. He is due to appear in court in Belfast on Wednesday, the PSNI said.Police Service of Northern Ireland Assistant Chief Constable Ryan Henderson told a press conference this afternoon that he is believed to have been granted Indefinite Leave to Remain (ILR) in the UK, having previously been in the Irish capital Dublin.The two countries on the island of Ireland are covered by the Common Travel Area, which allows British and Irish citizens to pass freely between both countries over an open border.DUP leader and East Belfast MP Gavin Robinson told the Commons today that the suspect was in the UK under a five-year visa.But Northern Ireland Secretary Hilary Benn said he did not know the answer to the 'legitimate question' of how he arrived here.Shadow home secretary Chris Philp said: 'Last night's brutal attempted beheading in Belfast is appalling. Northern Ireland Secretary Hilary Benn said he did not know the answer to the 'legitimate question' of how he arrived here'The Government must ensure full details about the suspect's nationality... and immigration status are released. 'Total transparency is required. If it turns out this man is an illegal immigrant it would provide further evidence that the Government's lack of border control is endangering the public.' The Daily Mail reported earlier this year how the CTA is being exploited by illegal migrants and smuggling gangs as a 'back-entry route' into the UK. Deputy Chief Constable Wendy Gunney, who leads the Domestic Organised Immigration Crime taskforce, said gangs also use it to move drugs and black market goods.There is no passport control between Britain and Ireland, although passengers are required to bring some form of photo ID and officials regularly carry out spot checks.Video of the graphic scenes in the north of the city were shared widely on social media last night provoking shocked reactions from the public and politicians of all parties.The violence unfolded outside an apartment block on Kinnaird Avenue, in the north of the city, at around 10.30pm on Monday. The footage shows a man standing astride a bloodied victim holding a knife to his throat and his fist in the air. As onlookers screamed he then starts making a sawing motion as witnesses say: 'He's trying to cut his head off.' Police said a kitchen knife was recovered from the scene.Then bystanders intervene including a man with a hurling stick who hits the suspect while others helped to subdue the man.A man in his 40s was rushed to hospital with serious injuries to his face, neck and back, and is said to be in a 'critical' condition.Mr Henderson told journalists the victim of the knife attack in Belfast suffered significant injuries to his eyes and serious slash wounds to his back and face after being attacked with a kitchen knife.'My understanding is that the individual came into Northern Ireland from Dublin, moving up, and then was granted leave to remain,' he said.He said the Home Office 'will be confirming that in more detail in due course'.'I share the public revulsion over the brutal nature of this attack, which has created concern not only here in Northern Ireland, but much further afield, and I understand also that there will be questions regarding the nature of the attack,' he added.There is nothing to suggest at this stage that the attack is terrorism-related, he said, and he went on to urge members of the public to be 'very mindful of what they share online' after graphic footage of the attack was posted.