A dawn car bombing claimed by the Islamic State group hit the finance ministry of the Saudi-backed Yemeni government on Wednesday, killing two guards and wounding four, a security source said.

In a statement on its Amaq propaganda arm, IS claimed the ‘detonation of a parked explosive-laden vehicle’ outside the ministry building in Yemen's second city Aden, the SITE Intelligence monitoring group reported.

Aden serves as the headquarters of the Yemeni government. Despite a Saudi-led military intervention launched in March 2015, the capital Sanaa and much of north of the country remain in the hands of Shia rebels.

The power vacuum has allowed both Al-Qaeda and its jihadist rival IS to bolster their presence in Yemen, particularly in the government-held south.

Aden has been hit by a spate of bombings that have killed hundreds of people, some claimed by Al-Qaeda and some by IS.

With US-backing, the Saudi-led coalition has expanded its campaign in Yemen to battle the jihadists in the south, but they retain control of parts of the mountainous and desert interior.

Al-Qaeda's Yemen-based arm is regarded by Washington as the jihadist network's most dangerous but IS has claimed a growing number of attacks in the impoverished Arabian Peninsula country over the past two years.