The Belgian crisis center in charge or coordinating security responses said that an alert had been circulated to all police forces in the country but there were no immediate plans to raise the security level to the maximum that would indicate an imminent threat of an attack, Reuters reported.
Newspaper DH quoted the alert from Belgium's anti-terror cell as saying the terrorists group "left Syria about a week and a half ago to reach Europe via Turkey and Greece by boat without passports", without giving an exact departure date.
The alert came two days after an attacker who pledged allegiance to Daesh killed a French police commander and his partner at their home outside Paris, and four days after a gunman declaring loyalty to the terrorist group massacred 49 people in a nightclub in the US city of Orlando, Florida.