David Ford said: “This despicable act illustrates a very nasty streak of racism and must be strongly condemned.
“The overwhelmingly warm response received following the announcement of Anna Lo as Alliance candidate for South Belfast is much more representative of local people. Anna is seen both as a very strong candidate in her own right and as a symbol of movement towards an integrated society.
“As a community, we must sent the strongest possible message to these thugs – they have no place in this society. Alliance has stood up against sectarianism for thirty years and we will also stand up against racism and any other form of discrimination.
“We are referring this matter to the police.”