Belgian police announced they had thwarted a major terror attack on Thursday.

Counterterrorism police raided a town east of Brussels on Thursday, killing two terror suspects and arresting a third one in a shootout.

The operation in the eastern town of Verviers was part of a crackdown on Islamic extremists returning from Syria, according to reports of CNN.

Eric Van der Sypt, Spokesperson for the Belgian national prosecutor’s office, made clear that the suspects, some of whom were believed to have recently returned from Syria, had opened fire on security forces who had been conducting the operation.

Van der Sypt said that two of the suspects had died in a shootout, while a third had been  seriously injured.

Police raided and searched a total of 10 locations in the town of Verviers and around Brussels, according to Bloomberg.

Belgium raised its terror alert to its second-highest level.

Earlier on Thursday, police detained a man suspected of supplying weapons to Amedy Coulibaly,the man who attacked a Paris kosher supermarket and was killed in a police raid on the site as part of the terror attacks that left 17 people dead in France last week.

The suspected arms dealer is in custody and further investigations are to show whether he is involved with the events in Paris.