Yemeni security forces carried out air strikes in which 30 suspected Al-Qaeda militants were reported killed in the south of the country on Wednesday and said they foiled a plot to attack embassies.

A Yemeni Red Cross worker was also killed in the air raids as he travelled in the south on a mission to help negotiate the release of a kidnapped French colleague, a relative told AFP.

The aircraft carried out several strikes, the mayor of Mahfed town on the outskirts of Abyan and Shabwa provinces, Yaslam al-Anburi, told AFP by telephone. "There were 30 deaths in Al-Qaeda ranks for sure."

"Yemeni aircraft carried out a series of raids against concentrations of Al-Qaeda fighters, mainly in the Wadi Dhiman and Dayda valleys, killing 30 and wounding many others," he said.

Earlier, a tribal chief said three suspected militants were killed and four wounded in an air raid targeting a group of Al-Qaeda fighters in a desert region between Abyan and Shabwa provinces.

Yemen's military launched a campaign in May against Al-Qaeda in the south which ended more than a year of jihadist control over a string of towns and villages in Abyan and Shabwa.

The group's fighters are believed to have retreated to safe havens in mountainous regions of Shabwa, Marib and Hadramawt provinces where they enjoy tribal protection.

Red Cross worker Hussein Saleh, killed in the air strikes on Wednesday, was in the region along with the head of the International Committee of the Red Cross for the southern port city of Aden, Saleh's relative said.

He was on a mission to help secure the release of a French ICRC employee who was abducted in April, he added, while the ICRC said Saleh died in unclear circumstances while on a humanitarian mission.

The ICRC delegation head in Yemen, Eric Marclay, added: "We are devastated by the tragic loss of our friend and colleague Hussein," who leaves behind a pregnant wife and four children.

On April 22, the ICRC said a French member of its staff was abducted in western Yemen. There has been no news of him since then.

More than 200 people have been abducted in Yemen in the past 15 years, many of them by members of the country's powerful tribes who use them as bargaining chips with the authorities. Almost all of them were freed unharmed.

Earlier, a security official said a plot to attack embassies in Sanaa had been foiled, state news agency SABA reported. "Three suspects armed with weapons, explosives and maps showing the (embassy) locations" were detained.

He said the residences of "military commanders and other important people" were also marked on the maps.

The reports came two days after a suicide bomber killed Salem Ali Qoton, the general who spearheaded the month-long offensive against Al-Qaeda in Abyan and Shabwa provinces.

Also on Wednesday, security forces said they arrested Majed al-Qulaisi, "a member of the (Al-Qaeda) cell that planned" a massive suicide attack that killed more than 100 troops at a military parade rehearsal in Sanaa last month.

A Tunisian, "one of Al-Qaeda's most dangerous foreign nationals in Yemen," Nizar Abdel Rahman, was also arrested, SABA reported.

After taking office in February, President Abdrabuh Mansur Hadi has pledged to destroy Al-Qaeda in the Arabian Peninsula, the network's local branch, which is considered by Washington as the group's most active and deadly.