Yemeni officials say gunmen have killed four senior security officers in the past 24 hours in a string of attacks.
The assassinations come as the Yemeni government pursues what officials say is a major campaign reportedly backed by U.S. drone strike in southern Yemen against al-Qaeda. The government says 55 suspected militants have been killed so far.
The officials say assailants riding motorcycles gunned down three colonels, two of them in the intelligence agency and one from military police in Sanaa on Monday and early Tuesday.
They say gunmen also shot dead a deputy security chief on Tuesday in the central city of Harib.
The officials spoke on condition of anonymity because they were not authorized to brief the media.
