BRUSSELS (REUTERS) - Belgian prosecutors charged three men with terrorism offences on Saturday (June 18) following overnight raids that took place amid heightened security in Belgium and France due to the Euro 2016 soccer tournament.

Three months after Islamist bombers killed 32 people in Brussels, police searched dozens of houses across the country and arrested 12 people the night before Belgium's Euro 2016 game against Ireland.

Nine of them were released after questioning but three Belgian nationals identified as 27-year-old Samir C., 40-year-old Moustapha B., and 29-year-old Jawad B., were charged with "having attempted to commit a terrorist murder and for participation in the activities of a terrorist group", the federal prosecutor's office said in a statement.

Some media reports said the suspects had planned attacks against fans watching the Euro 2016 games in Brussels, and had possibly been targeting Saturday afternoon's Belgium vs Ireland match.

Earlier on Saturday, Belgian Prime Minister Charles Michel chaired a meeting of the government's security council, which includes the ministers of defence, foreign affairs, home affairs and justice, after the raids and said soccer-related events would go on as planned with extra security measures.

"We want to continue living normally," Michel told a news conference. "The situation is under control."

"We are extremely vigilant, we are monitoring the situation hour by hour and we will continue with determination the fight against extremism, radicalisation and terrorism," he added.

No weapons or explosives were found during the overnight searches, which also involved 152 garage lockups.

SOCCER MATCHES TARGETED?

Flemish public broadcaster VTM said the people arrested overnight were suspected of planning an attack in Brussels this weekend during one of Belgium's soccer matches.

Areas where fans watch matches in Brussels were potential targets, as well as other crowded areas such as shopping centres and stations, Belgian media reported.

The Belgian crisis centre in charge of coordinating security responses decided not to raise the security level to the maximum that would indicate an imminent threat of attack, Michel said.

Public broadcaster RTBF said Belgium's crisis centre on Friday had placed several government ministers, including Michel, under heightened protection.

Michel said extra security measures had been taken for some people but did not name them.

With the Euro 2016 soccer tournament underway in neighbouring France, Europe is on high security alert. March's deadly attacks by Islamist suicide bombers in Brussels followed attacks in Paris last November in which 130 people died.

Investigators have found links between the Brussels and Paris attackers, some of whom were based in Belgium.

On Monday a French policeman and his police officer partner were stabbed to death outside their home in Paris in an attack claimed by Islamic State in Iraq and Syria.

In a video posted on social networks, the attacker, Larossi Abballa, linked it to the soccer tournament, saying: "The Euros will be a graveyard."

Two suspected associates of Abballa were placed under investigation on Saturday for membership of a terrorist organisation.

Separately, a judiciary source told Reuters on Friday a 22-year-old man suspected of planning attacks on tourists had been jailed on terrorism charges after being arrested at the start of the week.

On Wednesday, Belgian police received an anti-terror alert warning that a group of Islamic State fighters had recently left Syria en route for Europe planning attacks in Belgium and France, security officials said.