Rescue teams are desperately continuing their search for survivors buried under an apartment block in Ukraine.At least 19 people are known to have died in an explosion which destroyed the building. As many as 24 others are still missing. Oxygen canisters stored in the basement are being blamed. An eyewitness at the scene said: “In this house there lived my friend with his wife. He he repeatedly told me that plumbers used to store oxygen cylinders in the basement. And he even told me that one former occupant of the building wrote many times to authorities complaining about this, but then he got tired of struggling with the bureaucracy and moved away.’‘ The explosion took place overnight in the Black Sea resort of Yevpatoria in the Crimea. Emergency crews, stopping occasionally to listen for survivors, have so far managed to pull out 21 people alive from the rubble of the building. President Victor Yushchenko, who arrived in the town with Prime Minister Yulia Tymoshenko, has declared tomorrow a national day of mourning.