Europe is commemorating the 10th anniversary of the September 11 attacks on the United States amid heightened security after police in Sweden detained four people suspected of plotting a terrorist attack there. Four former Communist nations that joined the EU in the last decade are among the Union's member states commemorating the 9/11 attacks.
Eastern European nations Hungary, Slovakia, the Czech Republic, and Poland, joined countries around the world who are marking the September 11 attacks on the United States ten years ago.
At the time, Hungary was among the first countries to suggest that NATO should invoke its Article 5 following the attacks on the U.S. The Article suggests that an attack on one NATO member state should be seen as an attack on the whole alliance.
Now a decade later, Hungary's Foreign Ministry said in a statement that Hungary still "actively participates in efforts directed against international terrorism."
Hungary is holding a series of events, including a memorial concert in the Deak Square Lutheran church in Budapest, to commemorate the almost 3,000 victims of the September 11, 2001 attacks on the United States, and highlight continuing efforts to fight terrorism.
In neighboring Slovakia, the bells of the St. Martin?s Cathedral in the capital Bratislava and other churches began ringing Sunday at the the time that the first plane hit the World Trade Center in New York.
There were also commemorative events in the Czech Republic, such as a concert and exhibition at the Ministry of Foreign Affairs, showing the attacks in New York and Czech contributions to reconstruction efforts in Afghanistan.
In Poland, which currently holds the rotating presidency of the European Union, government officials were among those attending a wreath-laying ceremony in the capital Warsaw at a special memorial for those who died in the 9/11 attacks.
The ceremony was to be followed by a gala concert with music specially composed to remember the victims. One of Poland's most prominent veteran politicians, Jerzy Buzek, said it was important never to forget what had happened ten years ago.
Buzek is currently the president of the European Parliament.
"Our thoughts go to the victims and their families," he said. "Today we do not forget about the finest and bravest who risked and lost their lives in the rescue operations. Last but not least our special gratitude goes to those man and women who put everyday their lives in danger to make ours safer."
Sunday's events were overshadowed however by news that police in Sweden had arrested four people suspected of planning acts of terrorism there.
The detentions were announced after police evacuated an arts center in the country's second largest city of Gothenburg.
It comes amid an ongoing debate between Europe and the United States as to how far police surveillance and other security measures should go to prevent acts of terrorism. Buzek warned that it was crucial not to give up basic freedoms. "Over the last 10 years we have often been confronted with the question of the trade-off between freedom and security. We should never give in to the temptation of sacrificing freedom on the altar of security. If we did, what we are trying to secure would be void of value," he said.
He says no attack can shake those convictions and that the ?most promising signs? are those now coming from North Africa and the Middle East where calls for more freedom reverberate throughout the region.