ADEN, Yemen, Altogether seven civilians were killed, during armed confrontations between the security forces and unknown gunmen, in Yemen's southern port city of Aden on Tuesday, a security official told Xinhua.

The clashes took place in Sheikh Othman district of Aden, when special security forces launched a raid to apprehend a wanted man, suspected of links to the Daesh group, the security source said.

He said, following the anti-terror raid, a group of masked gunmen attacked a security checkpoint in the same neighbourhood, wounding at least three soldiers.

Other security soldiers arrived and engaged in a two-hour fighting with the unknown attackers.

The southern port city of Aden is the headquarters of Yemen's internationally-backed President, Abdu-Rabbu Mansour Hadi, and his government.

Aden witnessed several well-planned assassinations and armed attacks, after Saudi-backed forces drove the Shiite Houthi rebels out from the strategic city in July, 2015.

The newly-trained anti-terrorism troops, supported by United Arab Emirates' (UAE) armoured vehicles, made substantial achievements in recent months, disabling several explosive material factories used by terrorists to manufacture car bombs in Aden.

In addition, several commanders of the Yemen-based Al-Qaeda branch were captured, in successful raids conducted by the UAE-backed Yemeni forces in Aden and neighbouring provinces.

The Yemen-based Al-Qaeda in the Arabian Peninsula (AQAP), also known locally as "Ansar al-Sharia," emerged in Jan, 2009, claiming responsibility for a number of terrorist attacks against Yemen's army and government institutions.

The AQAP and the Daesh-linked terrorists, took advantage of the security vacuum and ongoing civil war to expand their influence and seize more territories in southern Yemen.

Security in Yemen has deteriorated since Mar, 2015, when war broke out between the Shiite Houthi group, supported by former President, Ali Abdullah Saleh, and government forces, backed by a Saudi-led Arab coalition.