Police in Belgium have arrested two suspected Islamist militants during raids but found no evidence they were planning an attack.
At least 16 people of mainly Chechen origin were initially detained but were later released.
The operation was triggered by one suspect seeking medical help for wounds believed sustained in Syria.
In January, Belgian police intercepted mobile phone messages between a group of suspected jihadist fighters.
Later that month officers killed two men who opened fire on them during a series of raids against an Islamist group that federal prosecutors said was on the point of launching attacks across the country.