Two Iraqi migrants drowned and four others were missing after their small boat capsized as they attempted to cross the Danube River from Bulgaria to Romania, the Bulgarian state radio reported Tuesday.
Among the missing are two girls. Four survivors swam ashore to a river island near the Bulgarian city of Ruse, the broadcaster said citing border police.
The accident occurred last week but went unreported.
The Iraqi group arrived from Turkey and had reportedly paid smugglers 10,000 dollars per adult and 7,000 dollars for each child to help them reach Germany.
Bulgaria became the main gateway for people aiming to get to wealthier parts of Europe after countries on the Balkan route - Macedonia, Serbia, Croatia, Slovenia and Hungary - sealed their borders to migrants in March.