At least 20 troops from a Saudi-led coalition have entered the Yemeni city of Aden to fight Houthi rebels, militia commanders have claimed.
The masked soldiers, dressed in black, landed between al Mansoura and the airport on a "reconnaissance" mission, and witnesses reported helicopter gunships hovering above the landing area.
According to a government official, another force is en route to Aden, which is located in Yemen's south. This is the first reported deployment of Saudi-led troops on the ground inside the country.
However, Saudi Arabia has denied any major ground offensive has begun in Aden, even though the coalition is continuing to assist militias fighting Houthi rebels.
Brigadier General Ahmed Asseri also said he could not comment on whether any special forces had been deployed to the city.
Meanwhile, according to Human Rights Watch report, a Saudi-led coalition may have used cluster bombs during airstrikes targeting Shia rebels.
The group claimed the munitions were supplied to Saudi Arabia by the US and landed "within 600 metres of several dozen buildings".
Cluster bombs usually spread bomblets over a wide area.
Some of them do not detonate on impact and explode at a later date, maiming or killing civilians.
Saudi Arabia has denied using such weapons.