The disorder in Northern Ireland since a knife attack in Belfast on Monday reached levels not seen since “the worst possible days of the Troubles”, the Police Service of Northern Ireland (PSNI) chief constable Jon Boutcher said.Boutcher said “racist, mindless, vile thugs” had committed acts against those who are “nothing but decent, law-abiding, positive members of this community”.The PSNI said “the streets of Northern Ireland need to return to calm and order” and called for those with influence to do “all in their power to get the thugs off our streets”. The police vowed to crack down on the violence that erupted in the wake of the stabbing.Hadi Alodid (30), a Sudanese national with an address at Duncairn Avenue in Belfast, was remanded in custody on Wednesday after being charged with the attempted murder of Stephen Ogilvie. Public order incidents on Wednesday night had seen 12 PSNI officers injured, with at least 16 people arrested. People were forced to flee their homes and multiple cars and homes were set alight in the first night of disorder on Tuesday.Businesses shut on Thursday afternoon, with bus and train services terminating early in the evening amid fears of further violence. The protests in Belfast, however, were limited to small, isolated groups of protesters blocking roads in the east of the city.The Northern Ireland police ombudsman said the force had fired 17 plastic bullets since the disturbances erupted, and it had opened an investigation into whether their use was proper. Amnesty International had expressed concerns about their use “with so many children on the streets”.Sham Supermarket on Blondin Street, which was attacked during the disorder on June 9th in Belfast. Photograph: Natalia Campos/AFP via Getty Images Condemnation for the disorder was widespread. Speaking at Stormont, DUP leader Gavin Robinson said the family of Stephen Ogilvie had “spoken very powerfully, in my view, that their desire is that what happened to their son on Monday evening is not used as an excuse for intimidation or division within our society”.Robinson said he met with Ogilvie’s parents on Thursday afternoon and the family were “broken” after what had happened to their son, who lost his left eye in the attack.Ogilvie’s condition is “improving” and he could be woken from a coma in coming days. Bilateral meetings between members of the Irish and UK governments, as well as the Northern Ireland Executive, focused on protecting the Common Travel Area (CTA) and stronger enforcement to “prevent abuse” of it in the wake of the stabbing.Minister for Justice Jim O’Callaghan, Stormont Justice Minister Naomi Long and UK secretary of state for Northern Ireland Hilary Benn spoke by phone on Wednesday, where the CTA was discussed, with agreement to co-operate further on the arrangement.O’Callaghan had stressed the “significant” border management operations taking place at Dublin Airport, the department said in a statement.“Minister O’Callaghan discussed the importance of cross-border co-operation in protecting the Common Travel Area for both Ireland and the UK,” it said.[ Newton Emerson: Northern Ireland’s politicians have no power over immigration. London controls it allOpens in new window ]Northern Ireland First Minister and Sinn Féin vice-president Michelle O’Neill said bad actors were “orchestrating hate and fear” online in the wake of the stabbing. O’Neill said these online actors “don’t care about our community” and were “not reflective” of society.Concerns remained around the need for a plan to address the unrest. Claire Hanna, the leader of the Social Democratic and Labour Party, said there was “no sense of a plan” to deal with the ongoing disorder, after speaking with Benn on Thursday.Hanna stressed the need for short-term plans to stop people from being “menaced on the streets and in their homes”, as well as a long-term “cohesion strategy”.