(ANSA-AFP) - BELGRADE, AUG 22 - Serbian police were searching for some seven missing people Thursday after a boat carrying migrants toward Bosnia on the Drina River capsized, police said. Serbia is one of the main transit countries on the so-called "Balkan route" on which migrants attempt to reach the European Union. It borders four EU nations. Early on Thursday a boat with about 25 migrants on board capsized near the border town of Ljubovija in Serbia, according to information from those rescued, police said in a statement. Police found 18 people on the riverbank, including three children, who managed to reach the shore, and rescuers were searching for the others. (ANSA-AFP).