SANAA Yemeni air force officers shut down the capital's airport on Saturday, stopping all flights in protest at the sacking of their commander, a half-brother of former President Ali Abdullah Saleh, an aviation official said.
A source on the military committee tasked with overseeing a planned restructuring of the army told Reuters the head of the air force, General Mohammed Saleh al-Ahmar, had refused to leave his post unless General Ali Mohsen al-Ahmar, an opponent of Saleh, was also fired.
The blockade of the airport was a direct challenge to the authority of President Abd-Rabbu Mansour Hadi, who replaced Saleh earlier this year and is trying to reform the army and remove Saleh allies from key posts in government and the military.
As part of those efforts, Hadi replaced nearly 20 top officers on Friday, including the air force commander, who was made assistant to the defence minister instead.
The General People's Congress (GPC) party headed by Saleh, which shares power with opposition parties in a unity government, said it had not been consulted on the reshuffle, which it described as biased.
"No consultation was undertaken with the GPC and its allies ... No agreement was reached on the decisions and there was no negotiation. The decisions that were issued comply with the wishes of one side," an unnamed GPC official was quoted as saying on the party's website.
Military vehicles full of air force staff loyal to their sacked commander encircled Sanaa airport at dawn on Saturday, turning passengers away and preventing flights from taking off or landing, witnesses said.
Demonstrators demanding the resignation of the same commander earlier this year brought several Yemeni airports to a standstill.
Transport Minister Waed Abdullah Bathib told Qatar's state news agency incoming flights had been diverted to the southern port city of Aden.
The airport closure highlights the challenges facing Hadi, whose reshuffle runs against the entrenched interests of Saleh's associates and those of rival General Ali Mohsen, some of whose allies were also sacked on Friday.
Mohsen was sanguine about the changes: "Yesterday's decisions serve the general interest... I fully comply with the decisions of the political leadership and the constitution and I will place no conditions in the event that the political leadership decides to remove me from my position," he was quoted as saying on the Ansar al-Thawra website, which is run by his office.
Once Saleh's right-hand man, Mohsen turned against him early last year along with part of the armed forces, sparking sporadic open combat on the streets of Sanaa with loyalist troops and tribal militiamen that threatened to push the country into civil war.
The reshuffle, which left Saleh's son and nephew in place as heads of key military units, was welcomed by United Nations and Gulf diplomats who helped hammer out the deal under which the former leader left office after months of anti-government demonstrations that paralyzed the impoverished state.
The diplomats said Hadi's move was in "perfect harmony" with the letter and spirit of the power transfer plan, according to a statement cited by state news agency Saba.
A committee responsible for demilitarizing Sanaa was dismantling checkpoints set up by the warring factions in the west of the city to enforce the withdrawal of armed tribesmen and troops from the streets by the end of the week.
Previous efforts to do this have failed.
Hadi faces a Shi'ite rebellion in north Yemen and an emboldened wing of al Qaeda concentrated in the south, which is also home to a separatist movement trying to revive a socialist state that Saleh united with the north in 1990.
Early on Saturday, Yemen's state news agency had been hacked, apparently by southern secessionist sympathizers. Instead of the usual news feed, there were pictures of southern leaders and the former southern state's flag.
"Your turn has come, all major Yemeni websites. If we do not see the southern flag waving above Yemeni sites we will eventually destroy them," read a statement posted on the site, which was later restored to normal.
Some southerners accuse northerners of pillaging their resources and discriminating against them. They want no part in the united Yemen envisaged by the Gulf initiative.
(Writing by Isabel Coles; Editing by Andrew Roche)