UEFA have announced the launch of an investigation into claims Manchester City players were racially abused by Porto fans during last week\'s UEFA Europa League match. City complained to European football\'s governing body that Mario Balotelli and Yaya Toure were the target of racist chants during the English side\'s 2-1 victory over the defending champions at Estadio do Dragao last Thursday. \"Following a complaint lodged by Manchester City FC, UEFA has today opened disciplinary proceedings against FC Porto for the improper conduct of supporters...during their UEFA Europa League round of 32 first-leg match against Manchester City FC last week,\" read a statement on the UEFA website. \"The UEFA Control and Disciplinary Body will deal with the case on 29 March.\" According to UEFA\'s disciplinary code, if found guilty, Porto risk a fine of €20,000 ($26,500) and could also be ordered to play one or more matches behind closed doors. The two teams will reconvene for the return leg in Manchester on Wednesday.