Bieber sings to Yolanda survivors

Pop megastar Justin Bieber sang to young survivors of the Philippines' deadliest typhoon on Tuesday after he flew into the disaster zone to boost an international relief effort.

Bieber flew unannounced to the central city of Tacloban just over a month after it was devastated by Super Typhoon Yolanda (international name: Haiyan) and sang Christmas carols to children at a local school amid tight security, witnesses said.