SANAA, Yemen (AP) -- 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-Qaida. 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 Tuesday in the central city of Harib.
The officials spoke on condition of anonymity because they were not authorized to brief the media.