Health officials say at least seven people killed and at least seven more injured in clashes in Ukraine . The indigenous ethnic minority Tatar population opposed the move . Mariupol 's acting interior minister says 39 militants killed , 4 detained in Mariupol . `` We will overcome all the difficulties , '' says Referendum President Vladimir Putin . Putin watches as warships and military aircraft take part in displays in Sevastopol , Crimea .
Health officials say at least seven people killed and at least seven more injured in clashes in Ukraine . Mariupol 's acting interior minister says 39 militants killed , 4 detained in Mariupol . `` We will overcome all the difficulties , '' says Referendum President Vladimir Putin . Putin watches as warships and military aircraft take part in displays in Sevastopol , Crimea .