Members of Russia's OMON (Special Force) beat a crowd of peaceful protesters in Moscow. .Police detained Garry Kasparov, the former world chess champion who now leads one of Russia's strongest opposition movements, and at least 100 other activists as they gathered for a forbidden anti-Kremlin demonstration in central Moscow..The demonstration, one in a series of so-called Dissenters' Marches, increased tension between opposition supporters who complain the Kremlin is cracking down on political dissent and authorities who vow to block any unauthorized demonstrations.