Al-Qaeda said in a statement that jihadists had opened fire on Sunday on two cars carrying four American military advisers who were in the Red Sea city on a training mission with the Yemeni Coast Guard.
The militants "opened fire on them as they left their hotel on their way to work," the militant group said, adding that the attackers were able to flee despite efforts by Yemeni security forces to cordon off the city.
A local security official confirmed the attack took place, but gave no further details.
The US embassy in Sanaa however denied the presence of American military advisers in Hudaida.
"Reports of US military trainers in Hudaida are false," an embassy email said.
Witnesses at the scene told AFP that three American military experts came under attack after leaving a local restaurant on Sunday. They said one man was critically wounded by a bullet to the neck.
An Arab diplomat in Sanaa said that the Americans were immediately evacuated but gave no further details on their current location.
US military experts are assisting the Yemeni army in an all-out offensive launched on May 12 to oust Al-Qaeda militants from the country`s restive southern Abyan province where they have seized control of several towns and villages.
So far, 213 people have been killed, according to a tally compiled by AFP, including 147 Al-Qaeda fighters, 31 military personnel, 18 local militiamen and 17 civilians.
The offensive was launched after newly-elected president Abdrabuh Mansur Hadi vowed to fight the network and followed days after the White House announced that a plot by Al-Qaeda in Yemen to blow up a US airliner had been foiled. (*)
Editor: Kunto Wibisono
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