Air force officers have shut down Yemen's main airport in protest at the sacking of their commander, a half brother of former President Ali Abdullah Saleh.
Military vehicles full of soldiers encircled the airport in the capital, Sanaa, at dawn on Saturday, turning passengers away and preventing flights taking off or landing.
Transport Minister Waed Abdullah Bathib told Qatar's state news agency that incoming flights had been diverted to the southern port city of Aden.
The airport closure was a direct challenge to President Abd-Rabbu Mansour Hadi, who replaced Ali Abdullah Saleh earlier this year and is trying to push through a restructuring of the armed forces to remove Saleh allies from key posts.
President Hadi dismissed air force head General Mohammed Saleh al-Ahmar on Friday and gave him the post of assistant to the defence minister.
A source on the military committee overseeing the armed forces' restructuring told Reuters the general had refused to leave his post unless General Ali Mohsen al-Ahmar, an opponent of Saleh, was also fired.
The armed forces split during the lengthy uprising against Saleh's rule, with some units openly siding with protesters.