Exactly 1,736 migrants were stopped in just four months, according to official government figures in a planned operation dubbed Medusa 2.
The operation was launched in October last year when authorities knew the French were in the process of closing the so-called Calais ‘Jungle’, the vast migrant camp which housed thousands of people who were hoping to make their way to Britain
Belgian Minister of Internal Affairs Jan Jambon of the conservative-nationalist N-VA (New Flemish Alliance) called the operation a success.
In an answer to parliamentary questions by Gautier Calomne of liberal French-speaking party Mouvement Réformateur (MR) Mr Jambon said that the number of illegal migrants charged dropped from 603 in October to 343 in January.
In November 451 were detained and 339 in December.
Mr Jambon said: “By studying the situation, effective collaboration with France, efficient and effective collaboration with all police services and the Aliens Office, it has been possible to prevent a flow of migrants arriving to our country.
“Following the dismantling of the Calais Jungle, the Medusa 2 action has undoubtedly had a very dissuasive effect.”
Some migrants had been exploiting a loophole in the Eurostar system which allowed people in Brussels to board the train without showing a passport, due to the Schengen agreement, if they simply bought a ticket to France.
However due to a lack of checks it was possible for people to simply stay on the train and carry on to London.
The scam is no longer possible, according to rail authorities, as passengers from Brussels to Lille now have to use coach 18, which is fully blocked off from the rest of the train, with personnel making sure everyone inside alights at Lille.
The Chairman of the SLFP Police Vicent Gilles attacked the Belgium administration though saying that the fall in the number of detainees was due to a drop in the number of staff carrying out the checks.
He said: “If the number of interceptions has decreased, it is simply because the number of staff carrying out controls has also decreased.”
The Medusa 1 plan which was launched in February 2016 intercepted 5,826 illegal migrants over five months in West Flanders.
Of the total, 4,924 were deemed to be “transit migrants” – people who were deemed to have no intention of settling in Belgium but travelling through the country.