The report by the London-based Al Arab daily said Monday that about 1,700 US troops arrived unexpectedly in the Yemeni capital, Sana’a.

Yemeni media say 1,500 US troopers were stationed in the Anad military base in the southern province of Lahij and the rest were sent to the Daylami airbase.

The reason behind the sudden increase of American soldiers and their mission remain unknown.

Reports indicate that Washinghton now has some 5,800 Marines on the ground.

The US has previously claimed to be fighting al-Qaeda-linked militants in the country. Washington says Al-Qaeda in the Arabian Peninsula (AQAP) threatens the region.

However, Yemeni citizens, rights groups and lawmakers have on various occasions condemned the presence of US Marine troops on Yemeni soil and the transformation of a five-star hotel in the capital, Sana’a, into a US military base.

Yemenis argue that the US move to bring in the Marines is merely a pretext for America’s domination on the ground.