Updated

Authorities in Britain, Belgium and Bulgaria have arrested some 25 people in overnight raids targeting smugglers who allegedly helped people immigrate illegally.

The U.K. Home Office says the operation Thursday morning involved suspects accused of transporting migrants, most of them from Afghanistan, across Europe and into the U.K.

Investigators arrested 11 people in Britain on suspicion of assisting illegal immigration. Eight more were arrested in Belgium and seven in Bulgaria.

Steve Dann, who directs the British agency that investigates immigration offenses tied to financial gain, described people smuggling as "a cruel and dangerous trade in which often vulnerable individuals are treated as commodities."

Dann says many migrants end up in the hands of "crime gangs who would seek to exploit them for modern slavery purposes."