The sporting world was quick to express solidarity with the victims of the deadly terror attacks in Brussels on Tuesday - violence that could throw the country's sports schedule into disarray.
"Horrified and revolted. Innocent people paying the price again. My thoughts are with the families of the victims. #Brussels," tweeted Belgium soccer captain Vincent Kompany.
"I wish for Brussels to act with dignity. We are all hurting, yet we must reject hate and its preachers. As hard as it may be."
At least 35 people were killed and more than 200 injured after two blasts at Zaventem airport in Brussels and a third explosion at Maalbeek metro station, close to EU headquarters.
The Islamic State group claimed responsibility for the attacks that came just days after the arrest of Belgian-born Salah Abdeslam, implicated in a coordinated assault in Paris in November that left 130 people dead and more than 350 wounded.
The Belgium soccer team, preparing for a friendly against Portugal next week in the Belgian capital, is lodged in a hotel close to the airport. Its training on Tuesday afternoon was canceled.
"#touseensemble, our thoughts are with the victims. Football is not important today. Training cancelled," the soccer federation said via its Belgian Red Devils twitter account.
Coach Marc Wilmots urged that "we stay strong together. My thoughts go to the families of those killed or injured".
"Unbelievable!" tweeted Kevin de Bruyne.
"My thoughts and prayers are with everyone affected by the horrific attacks on our city," said Divock Origi.
"I can't believe what happened this morning. My thoughts are with the victims, their family, friends and loved ones," said Thomas Vermaelen.
Friendlies in jeopardy
The federation has not indicated whether the March 29 friendly with Portugal will go ahead as planned.
A major security operation would have to be put in place for what is expected to be a jam-packed 40,000-seat stadium.
At Sunday's Cup final between Standard Liege and Club Brugge at King Baudouin stadium, police banned fans from bringing bags and searches were carried out on entry.
A friendly between the Netherlands and France scheduled for Friday in Amsterdam is also under scrutiny, according to the Dutch soccer federation, which said it would leave the ultimate decision to the government.
The last time France played at home was on Nov 13, a 2-0 victory over Germany quickly overshadowed by the attacks in Paris including three suicide bombers blowing themselves up outside the Stade de France as the game was going on.
France defender Laurent Koscielny said the team is united in solidarity with the Belgians and "does not fear for our safety".
"It's always difficult when you watch television and see such events," Koscielny said.
"The French federation has put in place a heightened level of security. We're calm.
"All the French people are with the Belgian people, as they were with us on November 13."
French Interior Minister Bernard Cazeneuve said security for the June-July Euro 2016 was already at a maximum and could not be increased further.
The Brussels attacks "remind us tragically of the high level of threat we are confronted with", Cazeneuve said.
"We cannot permanently raise what is already a very high level since January 2015, but we can strengthen the measures."
Cycling at risk
The cycling season in Belgium could also suffer at a time when thousands of people prepare to line the streets to watch their heroes compete in a raft of spring races.
The semi-classic 'Dwars door Vlaanderen' set for Wednesday was "provisionally" still set to be raced despite many riders having difficulties in reaching Belgium because of the closure of Zaventem International airport.
The E3 Harelbeke, a men's one-day race on the International Cycling Union's (UCI) World Tour, is due to be held on Friday, with the women's Gent-Wevelgem, scheduled for Sunday.
Like the soccer players, cyclists were quick to express solidarity. Former world champion Philippe Gilbert was racing the second stage of the Tour of Catalonia with a black armband.
"I feel for our dear friends in Belgium," tweeted UCI president Brian Cookson. "Our thoughts are with the families of the victims."
Thomas Bach, president of the International Olympic Committee, said: "The IOC strongly condemns these cowardly terrorist attacks.
"Our thoughts and our deep sympathies are with all the victims and their families and friends.
"Such odious attacks are directed against all human and Olympic values.
"We stand side by side with the Belgian and European people.
"These and other terrorist acts in different countries show that the Olympic values of understanding, respect and peace are more important than ever for our world."