Latvian police detained several supporters of Russia's radical National Bolshevik organization who were headed to downtown Riga to protest the meeting of the U.S. and Latvian presidents.
Several dozens of protestors were drawing close to security zone formed during Bush's visit in the city center when they were stopped by a row of police.
Protestors threw several smoke bombs, which spread a pungent white fume across the area.
Reporters on the scene said that police dragged some 25 youths into mini-busses as the latter resisted and shouted slogans.
Prior to the detention Riga's criminal police chief Ints Kuzis and his deputy Andrejs Grisins had tried to persuade the youth to disperse.
The protestors arrived from Grizinkals Park, not far from dowtown, where they had been holding a protest. Municipal police vehicles followed their procession from Grizinkals toward the center but did not disturb them until they reached the security zone.