Dec 13 (Reuters) - The Serbian FA (FSS) has been fined 80,000 euros ($104,700) and must play its next under-21 match behind closed doors after footballers and fans were found guilty of improper conduct, UEFA said on Thursday. The charges followed England's 1-0 victory in a European under-21 championship playoff in Krusevav in October. "The sanction against the FSS has been imposed for the improper conduct of its supporters during and at the end of the match, as well as for the improper conduct of the Serbia players at the end of the game," European soccer's ruling body said in a statement. ... More...