'Al-Qaeda attack' on Yemen army parade causes carnage
More than 90 people have been killed in a suicide bomb attack at a military parade rehearsal in Yemen's capital, Sanaa, defence ministry officials say.
The bomber, who was reportedly wearing an army uniform, blew himself up among a group of soldiers at al-Sabin Square, near the presidential palace.
An al-Qaeda source told the BBC one of its members had carried out the attack.
It was the deadliest incident in the capital since Abdrabbuh Mansour Hadi was elected president in February.
One of Yemen's security chiefs was sacked after the attack by a presidential decree.
Defence ministry officials say 222 people were injured in Monday's attack.
"We were in a parade, suddenly there was a huge explosion. Dozens of our men were killed. We tried to help them," Col Amin al-Alghabati told the Reuters news agency.
"The suicide bomber was dressed in a military uniform. He had a belt of explosives underneath," he added.
Another soldier, Ahmed Sobhi, told the Associated Press news agency: "This is a real massacre. There are piles of torn body parts, limbs and heads. This is unbelievable."
Security officials said the attacker had been a soldier taking part in the drill and that he had detonated his explosives shortly before Defence Minister Nasser Ahmed and the army chief-of-staff were expected to greet the troops.
Most of the casualties were from the Central Security Organisation - a paramilitary force commanded by Yahya Saleh, a nephew of former President Ali Abdullah Saleh.
Yahya Saleh was dismissed from his post just hours after the attack.
The soldiers had been practising for a parade for National Unity Day on Tuesday, which marks the anniversary of the 1990 unification of the Marxist People's Democratic Republic of Yemen - also known as South Yemen - and the Yemen Arab Republic, known as North Yemen.
"Yemenis must stand together in the face of this deadly terrorist threat," Brig Karim Nahil said. "We will celebrate our unity tomorrow with the blood of our martyrs on our hands and faces."
An al-Qaeda statement later sent to BBC Arabic said the group had recruited a soldier for the bombing, and that it was carried out in retaliation for "crimes" committed by the Central Security Organisation.
Monday's attack comes 10 days after the military launched an offensive against Islamist militants linked to al-Qaeda in the Arabian Peninsula (AQAP) in the southern province of Abyan.
Over the weekend, at least 33 militants and 19 soldiers were reportedly killed in clashes near the town of Jaar, in Abyan, which has been under control of Ansar al-Sharia - an offshoot of AQAP - since last year.
On Sunday, three civilian contractors training Yemen's coast guard were shot and wounded by unidentified gunmen as they drove through the eastern Red Sea port of Hodeida, the Pentagon said on Monday.
It said the injuries were minor.
Ansar al-Sharia has said it was behind the attack.
Ansar al-Sharia, or Partisans of Islamic Law, was founded in response to the growing youth movement in Yemen, which has marginalised Salafi jihadists who advocate the violent overthrow of the government.
In November, protesters forced President Saleh to hand over power to Mr Hadi, then his vice-president, as part of a deal brokered by the Gulf Co-operation Council.
Mr Hadi was elected president in February and immediately said one of his most important tasks was the "continuation of war against al-Qaeda as a religious and national duty".
The president has also moved to restructure the military, trying to purge it it of those closest to his predecessor.
In a separate development, Mr Saleh's General People's Congress party said he had been discharged after undergoing "routine" tests and "minor operations" at a hospital run by the Republic Guard on Sunday.
In June, Mr Saleh suffered serious wounds in a bomb attack on the presidential palace, for which he was treated in Saudi Arabia and the US.