Twenty migrants were found in good health in two separate trucks in Belgium on Saturday, according to local prosecutors.
Eleven African men, women and children - mainly from Eritrea - were found in a truck in the city of Saint-Trond, 65 kilometers (40 miles) east of Brussels, the Limbourg prosecutors said.
The truck, en route to the United Kingdom, stopped for a mechanical problem at a garage when the migrants were found.
Meanwhile, police also found nine men hidden in a truck in Bruges, in northeastern Belgium, en route to the port of Zeebrugge.
The men, who said they were Iraqi nationals, were also found in good health, according to the prosecutor of West Flanders quoted by the Belga news agency.
Because of its proximity to the UK, Belgium is frequently used as a route for migrants and trafficking networks.
Thirty-nine people were found dead this week in a refrigerated truck near London whose container had arrived from Zeebrugge.
Five people have been arrested in connection with the case.
Police on Tuesday also arrested three men of Iraqi origin suspected of trafficking 16 people in a van in the north western port city of Ghent, according to the Antwerp public prosecutor’s office.