The Islamic State group claimed a major attack Sunday on Yemen's government bastion of Aden, which left eight police officers dead and sparked a hostage crisis that continued well into the day.

The claim of the suicide attack on the security forces in the southern port city was made online by the extremist group's Aden and Abyan Wilayah, which said "clashes are still ongoing".

It came after Yemeni security sources said that they suspected Al-Qaeda militants were behind the attack.