Northern Ireland's chief constable has called violent loyalist protests against a republican dissident rally in Belfast "mindless anarchy and sheer thuggery".

Fifty-six police officers were injured and parts of central Belfast were wrecked overnight as thousands of loyalists sought to prevent a hardline republican alliance, the Anti Internment League, from passing down the city's main thoroughfare.

Chief Constable Matt Baggott accused loyalist rioters who attacked police with missiles, including scaffolding poles and paving stones ripped up from a main shopping district, of scarring the city's reputation.

He issued a challenge to politicians and community leaders to act like statesmen in the wake of Friday night's disorder and unequivocally condemn those responsible.

"I know that 99%, if not more, of the population will stand with me in utterly condemning those who scarred the reputation of our beautiful city last night," he said.

"Those people had no intention of peaceful protest, they lack self respect and they lack dignity."

Baggott, who warned that the "prisons would be bulging" once the police had identified and arrested those responsible, added: "The only voices we should hear now are those unequivocally condemning the violence and supporting fully the actions of the police and the rule of law and I don't want to hear any excuses for the disgraceful scenes that took place last night, because quite frankly there aren't any."

The Northern Ireland secretary, Theresa Villiers, also condemned the violence as shameful and called it "a hugely regrettable step backwards" for the province.

Tensions remain high this weekend with another controversial parade taking place on Sunday in the County Tyrone town of Castlederg. Local unionists will protest against an IRA commemoration organised by Sinn Féin.

The deputy first minister, Martin McGuinness, has promised that the march will be dignified but hundreds of unionists are expected to protest against it.

The Police Service of Northern Ireland (PSNI) forced the Anti Internment League to reroute its march away from Royal Avenue, a usually busy commercial street near City Hall, on Friday evening in the face of sustained loyalist violence.

During the disorder in Belfast an Ulster Unionist member of the Northern Ireland assembly, Michael Copeland, was struck with a police baton along with his wife and daughter. Copeland has claimed that a female police officer told him to "fuck off back to the slums" during the incident. He said he had taken down the officer's serial number and intended to make a complaint. The police have referred the incident to the ombudsman.

From 6pm on Friday to late into the night, PSNI officers in riot shields and body armour were bombarded with bricks, bottles, stones, fireworks, marbles fired from catapults and smoke bombs at the junction of Royal Avenue and North Street – the latter a main route into the loyalist Shankill Road area.

The PSNI responded by firing baton rounds and using batons to try to clear the loyalist demonstrators off Royal Avenue. They also drenched rioting loyalists with water cannon and used dogs to control the crowds.

During one attack, two officers were knocked to the ground on the frontline at North Street and paramedics spent at least 40 minutes tending to one officer who was later taken away in an ambulance wearing a neck brace.

On the fringes of the riot a number of extreme loyalists linked to a hardline fundamentalist Protestant preacher threatened several journalists, including the Guardian.

While loyalists set fire to bins and attacked a local pub, raiding the bar for pint glasses that they rained on police, the PSNI held back the anti-internment rally as it entered North Queen Street in the republican New Lodge district. Among those on the march were prominent dissident republicans from organisations aligned to the New IRA.

Eventually the PSNI redirected the dissident republican march into the nationalist Carrick Hill, where there was another standoff during which a small group of loyalists broke through and exchanged missiles with republican youths. After marshals on the republican side pushed the youths back, the rally was allowed to proceed across into Millfield, close to the bottom of the loyalist Lower Shankill area.

As the republican parade passed through towards the Lower Falls loyalists were penned back into North Street but continued to shower the marchers and police with missiles. By then the loyalists had set alight several cars in North Street.

Several thousand dissident republicans and their supporters along with two bands then marched up the Falls Road to a rally organised to commemorate the 42nd anniversary of the introduction of internment. The march was also seen as a measure of how much support the various factions of dissident republicanism enjoy in nationalist communities in the north.

The loyalists, meanwhile, continued to attack police long after the republicans had crossed from north to west Belfast.

The PSNI later confirmed that officers had fired at least 20 plastic baton rounds to quell the disorder around the centre of Belfast.

Speaking about Sunday's planned march in Castlederg, a campaigner for the Omagh victims accused Sinn Féin of double standards for organising an IRA commemoration for two men killed while trying to bomb another County Tyrone town 40 years earlier.

Michael Gallagher, whose son Aidan was killed in the Omagh massacre, questioned how Sinn Féin could condemn the Real IRA for the 1998 atrocity but laud two Provisional IRA who tried to blow up Castlederg in 1973.

"It is very sad that on all sides there is a ratcheting up of tension and worsening divisions by holding all these parades, whatever political persuasion they are. I think it is double standards to say that you stand by the victims of the Omagh bomb but then praise the actions of others who wanted to bomb another town," Gallagher said.

He added: "I can understand the hurt of the people in Castlederg about this march because 29 people lost their lives in the IRA campaign down there. That is the same number of victims caught in the bomb in Omagh many years later. It doesn't matter whether it was in 1973 or 1998 - it was wrong then and it is wrong now."

Earlier this week Gallagher and his fellow Omagh campaigners revealed evidence that the FBI, MI5 and the Garda crime and security department withheld vital information from police in Northern Ireand in the run up to the atrocity on 15 August 1998. Intelligence passed on from two informers inside the Real IRA was not shared with the old Royal Ulster Constabulary.