Traditional New Year's Eve fireworks in central Brussels have been canceled due to a continuing terror threat in the Belgian capital, officials said Sunday. The popular downtown Christmas market will close early, at 6 p.m., on December 31 rather than staying open all night, and the adjacent skating rink will shut at 8 p.m. Authorities warned of an increased risk of attack after police last week detained 14 people suspected of plotting to help an accused al-Qaida militant break out of jail. The inmate, Nizar Trabelsi, 37, is a Tunisian ex-professional soccer player who is serving 10 years for plotting to drive a car bomb into the cafeteria of a Belgian air force base housing about 100 US military personnel. However, in a letter published by the daily newspaper La Derniere Heure, Trabelsi denied that his supporters were plotting his jailbreak or any terror attack. A judge ordered his supporters' release for lack of evidence, and all suspects have maintained their innocence. "We've reviewed the situation and the conclusion is that there is no reason to scale back the current level of (terror) alert," said Jaak Raes, director general of the government's Crisis Center. "The aim is not to create panic ... but to avoid unnecessary risks." The government said last week it had information that the suspects were plotting to use explosives and other weapons to free Trabelsi, who was arrested in Brussels in 2001, two days after the Sept. 11 attacks, and convicted two years later. Prime Minister Guy Verhofstadt warned that the suspects also could have other targets in mind, and ordered police to step up security at the airport, in subway stations and at the Christmas market. During his trial, Trabelsi admitted plotting to kill US soldiers based in northeastern Belgium, saying he had met al-Qaida leader Osama bin Laden in Afghanistan and asked to become a suicide bomber. Trabelsi came to Europe to play professional soccer in 1989. Over the next few years, he bounced from team to team in the minor leagues, acquiring a cocaine habit and a criminal record. Eventually, he made his way to al-Qaida training camps in Afghanistan, where evidence presented at his trial showed he placed himself on a "list of martyrs" ready to commit suicide attacks.