Belgian prosecutors say they have detained four suspected Islamic State group recruiters, who they say may have planned new attacks in the country.

The Federal Prosecutor's Office said in a statement Wednesday that all four were charged with participating in the activities of a terrorist group. Two were ordered arrested by an investigating judge, one was released under strict conditions and one was released with an electronic bracelet.

The statement said the four don't appear to have links to the suicide bombers who struck the Brussels Airport and subway on March 22, killing 32 people.

Prosecutors said initial findings of the investigation indicated there may also have been plans for attacks in Belgium, but provided no details.

Searches were carried out in the city Antwerp and in two other locations.