Unidentified gunmen assassinated on Sunday a senior security official in the southern city of Aden, Yemen nearly two weeks after Prime Minister Moin Abdul Malik returned to the city.

Russian Sputnik news agency quoted security sources as saying that director of a criminal investigation in Mansoura Directorate in Aden, Major Salah al-Hujaili had been shot dead by unknown gunmen in the Eyadat neighbourhood.

According to the sources; al- Hujaili was shot dead by masked gunmen on a motorcycle in front of his house.

In January 2016, al-Hujaili survived an assassination attempt using an improvised explosive device planted in his car.

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The interim capital of Aden witnesses a major security vacuum and widespread crimes after the UAE- backed southern transitional council forces controlled the city and its security and military services on August 10.

On November 5, the Yemeni government and the Southern Transitional council signed an agreement which arranges the political, economic, military and security aspects between them.

However, so far the agreement has not been implemented mainly because the transitional council forces prevent the return of many government ministers to the city.

According to UN reports, between 2015 and 2019, there have been more than 100 assassinations in the south of Yemen.