Unidentified gunmen killed a Yemeni intelligence colonel in a drive-by shooting early Saturday while he was leaving home for work in the southern province of Lahj, a security official told Xinhua. \"About two unknown attackers armed with assault rifles killed Colonel Hussein al-Mansory after he left home in the outskirts of Lahj province,\" the security source said on condition of anonymity. A local government source confirmed to Xinhua that \"masked gunmen shot the intelligence colonel with one bullet ... and he could not survive.\" No group has so far claimed responsibility for the attack, but assassinations are more and more frequently carried out by al- Qaida militants in their fight against the Yemeni government forces. More than 70 intelligence and security officers have been killed in hit-and-run attacks in the past two years, according to recent statistics by the Yemeni interior ministry. The Yemen-based al-Qaida in the Arabian Peninsula, which emerged in January 2009, is considered the most strategic threat to the country and its neighboring oil-rich Saudi Arabia.