The development came as Yemen intensified its campaign to drive Al-Qaeda militants from their strongholds across this impoverished Arabian Peninsula country.

According to a statement by Yemen's Supreme Security Committee, the suspect gave himself up late Sunday in the province of Marib, surrendering to the local governor there.

The suspect was identified as Hamza Ali Saleh Al-Dayan, who is believed to have trained suicide bombers and helped plan the July 2007 suicide attack that killed seven Spanish tourists and two Yemenis in the same province.

Al-Dayan was among 23 Al-Qaeda members who escaped from a Yemeni jail in Feb. 2006, through a tunnel dug under the prison. He was later accused of taking part in the 2008 mortar attack against the US Embassy in Sanaa that killed a policeman and a young girl at an adjacent school. He and three accomplices fled in a car after that attack.

On Saturday, another suspected Al-Qaeda operative, Ghalib Al-Zayedi, surrendered after lengthy mediation efforts to Marib's Gov. Naji bin Ali Al-Zayedi, who is also his cousin.

Ghalib Al-Zayedi was arrested in 2003 and spent the next three years in detention after being accused of hiding a man believed to be Al-Qaeda's number two in Yemen.

The 2006 prison bust helped strengthen Al-Qaeda's offshoot in Yemen. In January 2009, it got another boost by merging with Saudi Al-Qaeda militants to form Al-Qaeda in the Arabian Peninsula.

The two surrenders also come against the backdrop of Yemen detaining several foreigners, including Britons, Americans, and an Australian woman, in connection with an investigation into Al-Qaeda's increased activity in the country.