A Yemeni affiliate of the Islamic State of Iraq and the Levant (ISIL) group has claimed responsibility for Tuesday's attack on an Arab coalition base that killed at least 15 troops, including four UAE soldiers.
The group made the claim through its affiliated accounts on Twitter on Tuesday, posting a series of photos depicting the bombings and pictures of the suicide attackers involved.
"Four martyrdom operations targeted a gathering of Saudi, Emirati, and Yemeni offices," a statement released by the group said.
The names of the attackers in the pictures suggested those involved were all Yemeni in origin.
Al Jazeera's Hashem Ahelbarra, who has reportedly extensively from Yemen, said the claim of responsibility by ISIL marked the start of "strange scenario" in Yemen.
"On the one hand, we have government forces and the Saudi-led coalition fighting the Houthis, and now you have ISIL fighting the government and Houthi forces," he said.
"You'll have the [southern] secessionists fighting al-Qaeda, and ISIL fighting al-Qaeda at the same time ... It will be a complete nightmare scenario in the near future.
"In 2014 ISIL emerged saying that they were there to defend Sunnis who had been undermined by the Shia ... they were present in the capital Sanaa, but now they're trying to build a platform in the south."
The explosions hit a hotel housing Yemeni officials and a Gulf military base in Aden, a government spokesman and residents said, in the biggest attack on the government since it retook the city from its Houthi foes in July.
Vice President Khaled Bahah, who is also prime minister, and cabinet colleagues escaped unharmed from what he said were car bomb attacks.
"Today's attack does not affect anybody. On the contrary, it binds us together more," he told a cabinet meeting afterwards in comments carried by Al Arabiya television.
The orphans of Yemen's war
Members of the Gulf Arab coalition have been providing security at the luxury al-Qasr Hotel, and Yemeni government officials' presence there makes it a highly symbolic target.
UAE officials earlier in the day blamed the Houthis and their ally, former President Ali Abdullah Saleh, for the attacks.
ISIL also claimed responsibility for an attack on a mosque in the capital, Sanaa, saying the target was Houthis going to the battlefront.
Seven people were killed in the attack on al-Nour Mosque in al-Nahda district, the Houthi-run state news agency said.
Christopher Swift, a professor of security studies at Georgetown University in the US, questioned ISIL's role in the Aden attack and stressed that the claim of responsibility needed to be verified.
"Organisations like ISIL, like al-Qaeda in the Arabian Peninsula, have a strong interest in making it look as if they're everywhere, even if they're not everywhere," he told Al Jazeera.
"One of the ways in which they do that is through social media, through propaganda, through information operations.
"Over the last few months, we have definitely seen ISIL make a play for the Yemeni theatre. But we haven't seen a large number of fighters going to Yemen."
ISIL has previously attacked mosques associated with Zaydi Muslims, the branch of Shia Islam the Houthis adhere to.
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Supporters have also carried out attacks in Saudi Arabia and Kuwait.
In August, at least 15 people including Saudi soldiers were killed when ISIL operatives attacked a mosque used by Saudi special forces in a region bordering Yemen.
The Arab coalition has been carrying out air strikes against the Houthis and their allies since March.
The UAE and other members of the coalition see Yemen's second-largest city of Aden as a key foothold in restoring Yemen's government to power as they and their Yemeni allies attempt to push the Houthis from Sanaa.
The war has taken a heavy toll on Yemen. More than 4,000 people have been killed, and the humanitarian crisis has left the impoverished country on the brink of famine.
Source: Al Jazeera And Agencies