Brussels - Belgian security authorities believe that a terrorist attack on the country is possible over Christmas after 14 suspected extremists detained earlier in the week were released, the Interior Ministry said on Saturday.
The country's security services have been put on a higher alert level until January 2, but citizens have been told that there is no need to panic.
Reinforced police patrols are to operate in public places, such as Christmas markets, shopping areas and bus and train stations.
Security personnel at the capital's transport companies have been placed on elevated alert as is normally the case when EU summits are held in Brussels.
The 14 suspected Islamic extremists were released overnight after being held on suspicion of planning to break a former footballer, Nizar Trabelsi, out of the prison to which he was condemned for 10 years for planning an attack on a Belgian military base in 2001.
A spokesperson for the public prosecutor's office said that searches of the suspects' homes had uncovered documents but no weapons or explosives.
One of the detainees was the widow of a suicide attacker who in 2001 killed Ahmed Shah Masud, who as head of Afghanistan's Northern Alliance had been fighting the Islamist extremist Taliban in central Asian country.
"We had sufficient evidence for a terrorist threat and therefore did not hesitate to arrest suspects," the spokesperson said.
No need to panic the populace though, after all this is "The Religion of Peace" we're talking about, just go back to sleep.