WASHINGTON (CNN) -- The U.S. State Department Tuesday advised Americans traveling in Northern Ireland to observe "increased caution" due to civil unrest that began when the Parades Commission barred a Protestant group from marching through a Catholic neighborhood in Portadown.

"American citizens are not a target of these protests, but increased caution is advised for any Americans visiting Northern Ireland as there is a possibility of simply getting caught in the wrong place at the wrong time," the State Department announcement said.

The announcement said that the dates of July 13 (when more marches are scheduled throughout Northern Ireland) and August 8 (when a traditional march against the walls of Derry is planned) may pose "particular potential for trouble."