Belgian authorities have freed three people after questioning them about a suspected plot to carry out extremist attacks in Brussels over the Christmas and New Year's holidays.

The releases were announced Friday by the Federal Prosecutor's Office. The three were among six people taken in for questioning on Thursday. The others who were interrogated were released Thursday.

According to prosecutors, the plot is suspected of targeting police, soldiers and famous locations in the Belgian capital, including its bustling central square, the Grand Place.

Two people, including the suspected leader, have been arrested, and a judge on Thursday ordered both men held for another month.

Because of the continuing threat, Brussels city officials canceled the New Year's Eve fireworks display and related public events Thursday night.