The Yemeni army foiled on Saturday a car bomb attack on the Anad air base used by US soldiers in the southern province of Lahj to train Yemeni forces in combating terrorism, officials said.

"We foiled an attack by a car packed with explosives that managed to breach several security checkpoints leading into the air base," said a military official who spoke on condition of anonymity.

He said "Americans on the base were the target of the attack."

According to the official, some "15 American soldiers have been on the base for two months training Yemeni forces in combating terrorism."

The car was "disarmed" and an investigation launched, he said, without reporting any arrests, though the army "suspects Al-Qaeda" was likely to be responsible.

The defence ministry confirmed the incident and accused the militant group for planning an assault on the base.

"The military police defeated an afternoon attack on the Al-Anad base," the ministry website quoted Lahj governor Ahmed Abdallah al-Majidi as saying.

"The vehicle belongs to Al-Qaeda," Majidi said, adding that its seizure led to "large quantity of explosives, gas cylinders and anti-tank rockets and clothes for female drivers."

The car was discovered Saturday in a wooded area of the air base though it appears it had been "smuggled in several days ago," the military official added.

He said that according to their information, "the attack was to be implemented today (Saturday)."

He did not explain why the attackers failed to detonate the explosives immediately after the car was smuggled into the base.

Taking advantage of the weakening of central government control by an Arab Spring-inspired uprising last year, Al-Qaeda overran most of southern Yemen's Abyan province, seizing its capital Zinjibar and several other towns.

On May 12, under orders from President Abdrabuh Mansur Hadi, the army launched a massive offensive to recapture territory lost to the militants.

Western diplomats at the time said US experts were assisting the army in their battle to destroy Al-Qaeda in the Arabian Peninsula, the network's local branch, considered by Washington to be the deadliest and most active.

The United States also continues to target militants using unmanned drones against AQAP.

On Thursday, a drone strike blasted two cars carrying suspected Al-Qaeda gunmen in the southern Yemeni province of Shabwa, killing five of them, a tribal chief and witnesses said.

The United States is the only country that has drones in the region, but Washington has never formally acknowledged the presence of troops in Yemen to assist in the offensive against Al-Qaeda.

Although weakened, Al-Qaeda continues to launch hit-and-run attacks on government and civilian targets across Yemen.

On October 2, Yemeni forces killed three suspected Al-Qaeda militants in a raid on their hideout in Aden, foiling a major plot to blow up targets in the restive southern port city.

Security officials said two vehicles packed with explosives and three suicide belts were discovered at the hideout, described by one official as an "Al-Qaeda explosives workshop" and a "base for planning and organising attacks."

In recent months, Al-Qaeda has carried out a spate of deadly attacks against Yemeni army and intelligence officials. These included a suicide attack earlier this year that killed General Salem Ali Qoton, the man charged with leading the offensive against Al-Qaeda.