KIEV, March 16 - Ukraine's new leaders announced on Sunday a call-up to raise 20,000 men for a newly-created National Guard, accusing Russia of sending "touring" trouble-makers across the border to stir up separatism in the country, Reuters reported.

Keeping tension high as pro-Russian Crimean leaders staged a referendum for the peninsula to secede to Russia, pro-Western Prime Minister Arseniy Yatseniuk pledged to bring to justice all those trying to destroy Ukrainian independence "under the cover of Russian troops.”

Earlier, acting defense minister Ihor Tenyukh said Russia was pressing ahead with a military build-up in Crimea in violation of an agreement covering basing rights for its Black Sea fleet which has been there since Soviet times.