Extensive police checks were carried out at Belgian and French train stations on Tuesday morning, Belga News Agency reports.
The operation was jointly conducted by French and Belgian officials in and around the West Flanders city of Kortrijk and the nearby French city of Tourcoing. Its stated objective was to find drugs, weapons and stolen items.
Over 1,000 passengers were questioned or investigated. Nine were found to be possession of drugs, one was discovered to be an undocumented resident, and another received a formal caution for disturbing public order.
Local Belgian officials praised the operation as "successful", adding that the "skills and experiences" of the French and Belgian police forces were highly complementary.
"The collaboration between our police officers and those from France provided added value," they said.
The latest operation follows the police crackdown last month at the Gare du Midi in Brussels, following reports of increasing criminality in the area. More than 60 arrests were made.
