Shiite rebels 'seize city of Taiz and airport'
Shiite rebels backed by supporters of former president Ali Abdullah Saleh have taken over parts of Yemen's third largest city of Taiz and its airport.
The UN Security Council is holding an emergency meeting on Yemen's security situation.
It comes after the US announced it was withdrawing its troops from Yemen due to the worsening security situation amid mounting violence by armed rival groups including Houthi rebels, al-Qaeda and Islamic State militants.