In this photo taken on Saturday, March 26,  and made available on Sunday, May 27, 2016, Italian Police arrest a man, kneeled at right, in the southern city of Bellizzi, near Salerno, Italy. Police identified the man detained as Djamal Eddine Ouali, an Algerian wanted in Belgium for facilitating illegal migration linked to the recent terror attacks in Paris. According to police he was sought under a European arrest warrant for alleged involvement in a network in Brussels which makes false documents, including those used by extremists implicated in the Paris and Brussels attacks. (Carmine Cappetti/www.asalerno.it via AP Photo) MANDATORY CREDIT
In this photo taken on Saturday, March 26, and made available on Sunday, May 27, 2016, Italian Police arrest a man, kneeled at right, in the southern city of Bellizzi, near Salerno, Italy. Police identified the man detained as Djamal Eddine Ouali, an Algerian wanted in Belgium for facilitating illegal migration linked to the recent terror attacks in Paris. According to police he was sought under a European arrest warrant for alleged involvement in a network in Brussels which makes false documents, including those used by extremists implicated in the Paris and Brussels attacks. (Carmine Cappetti/www.asalerno.it via AP Photo) MANDATORY CREDIT Credit: Carmine Cappetti

BRUSSELS — Belgian riot police clashed Sunday with hundreds of right-wing hooligans at a temporary shrine honoring victims of the Brussels suicide bombings, as investigators launched fresh anti-terror raids, taking four more people into custody.

Police used water cannon when scuffles broke out in front of the Bourse, which has become a symbolic rallying point for people to pay their respects to those who died in Tuesday’s attacks. Black clad men carrying an anti-Islamic State group banner with an expletive on it trampled parts of the shrine, shouting Nazi slogans. Ten were arrested and two police officers injured.

“We had 340 hooligans from different football clubs who came to Brussels and we knew for sure that they would create some trouble,” Police Commissioner Christian De Coninck said. “It was a very difficult police operation because lots of families with kids were here.”

Brussels mayor Yvan Mayeur expressed his disgust, with Belgium still in mourning over the suicide bombings at Brussels airport and subway, which killed at least 31 people and injured some 270.

“The police were not deployed to protect people from these hooligans but a whole other threat,” said Mayeur told RTL television.

People trying to pay their respects were also dismayed.

“It was important for us to be here symbolically,” said Samia Orosemane, a 35-year-old comedian. But, she added, “there were lots of men who were here and doing the Nazi salute, shouting ‘death to Arabs’ and so we weren’t able to get through.”

“We are all here today for peace, and for the brotherhood among peoples. Not for right-wing ideas. It’s neither the time nor the place,” said Theophile Mouange, 52.

Federal prosecutors, meanwhile, said Sunday morning’s raids were linked a “federal case regarding terrorism” but did not specify whether it had any links to the March 22 attacks.

Thirteen raids were launched in the capital and the northern cities of Mechelen and Duffel. An investigating judge was to decide later whether to keep the four in custody. Five were released after questioning.

Suspected plotters also were arrested Sunday in Italy and the Netherlands, though few details of their activity were released immediately.

Tuesday’s bomb attacks are also tearing at the fabric of the government, justice system and police, and Belgium’s interior minister sought Sunday to contain the growing criticism of the government’s handling of the tragedy.

Interior Minister Jan Jambon conceded Sunday that decades of neglect had hampered the government’s response to violent extremism. He said the government has invested $670 million into police and security services over the past two years but that Belgium’s justice system and security services are still lagging behind.

Jambon, whose offer to resign Thursday was declined by the prime minister, also acknowledged some shortcomings prior to the attacks.

“There have been errors,” he said on VRT television.

Jambon said it takes time to hire anti-terror specialists and specialized equipment and insisted that the government’s new investments need time before they become visible to the public.

As international pressure on Belgium has mounted for serving as an unwitting rear-base for extremist fighters who launched the Nov. 13 massacres that left 130 dead in Paris, the government has felt forced to defend its choices and the actions of investigators. Lawmakers, meanwhile, are demanding an inquiry.

Belgian investigators have been slammed for not questioning Abdeslam long enough or hard enough after he was shot in the leg during his arrest.

Police have also been criticized for taking too long to get to Zaventem airport on Tuesday morning after two suicide bombers blew themselves up there — and left an even bigger third suitcase full of explosives that did not go off.