Among those shot and killed over the weekend were the head of the security of the presidential palace in Taiz, Brigadier General Saddam Hussein al-Dahiri, and police chief Abdullah Gaithallah.

Sources told the Reuters news agency that gunmen in a car shot al-Dahiri as he left work, while Gaithallah was ambushed in his car in the southern province of al-Baida.

The Yemeni government confirmed on Sunday that an attempt on the life of Yassin Said Noaman, an adviser to President Hadi, was made a day earlier in the capital, Sanaa. A sniper targeted Noaman's car, but the vehicle was armored. Initial information indicated the shots were taken from the roof of a mosque near Noaman's home. As well as his position close to Hadi, Noaman is secretary general of the Socialist Party.

"Targeting such a well-known political personality and important national figure is targeting the move towards reform that Yemen is currently undergoing," local news agency Saba quoted a government source as saying.

The attacks come just days after a group linked with al Qaeda claimed responsibility for an assault on Yemen's Defense Ministry. At least 56 people were left dead on Thursday and more than 200 injured when a car bomb was detonated and gunmen stormed a military hospital within the ministry's headquarters, gunning down doctors, nurses and patients.

Al Qaeda in the Arabian Peninsula swooped to gain control of territory in the south during the 2011 uprising against former president Ali Abdullah Saleh. They said it targeted the complex because it housed Americans.

ph/pfd (Reuters, AFP, AP)