An explosion at a coffee bar near the U.S. Embassy in Tirana injured a waitress.
The explosion, caused by 10 grams (0.35 ounces) of dynamite, slightly injured waitress Violeta Pano, 50, and damaged Bar Deus, located meters away from the U.S. Embassy in the Albanian capital, according to a police statement.
Police are investigating who was responsible and what sort of device was used.
Though not officially acknowledged, Albanian and U.S. intelligence services are closely collaborating ahead of President George W. Bush's visit to the country June 10.
The choice of the city of Helsinki is not incidental as the capital of Finland had hosted US-Soviet negotiations on the limitation of nuclear stockpiles in 1969