Ukrainian president arrives in southeastern city of Mariupol: press secretary

MOSCOW (Reuters) - Ukrainian President Petro Poroshenko arrived in the southeastern city of Mariupol on Monday, his press secretary Svyatoslav Tseholko wrote on his Twitter microblog. Ukrainian troops have come under fire from pro-Russian rebels on the eastern edge of the city, a strategic city on the Sea of Azov. (Reporting by Thomas Grove, Editing by Timothy Heritage)