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ADEN, Yemen, May 15 (Xinhua) -- The death toll in Sunday's suicide bombing attack that took place near the gate of a registration camp for police recruits in Yemen's southeastern province of Hadramout rose to 30, a provincial security source said.

"The latest report concerning the casualties from today's suicide bombing attack that occurred near at the main gate of a police recruitment center in Mukalla mounted to 30 deaths and 70 wounded," the source told Xinhua on condition of anonymity.

The Yemen-based affiliate of the Islamic State (IS) group has officially claimed the suicide bombing that targeted police recruits in Hadramout.

According to the short statements revealed by the IS accounts on Twitter "about 40 apostates were killed when an Islamic State fighter detonated his explosive belt inside their military base in Mukalla."

The bloody attack occurred as a suicide bomber mingled with a group of new recruits in a police base near the presidential compound in the coastal city of Mukalla, Hadramout's provincial capital, the official said on condition of anonymity.

The toll could rise even higher as ambulances were evacuating the victims and dozens of critically injured people to nearby military hospitals and medical centers, according to the sources.

Meanwhile, witnesses told Xinhua that the commander of Hadramout's police forces Brig. Mubarak Obthani escaped a roadside bomb near his office in Mukalla.

On Thursday, three suicide bombers launched coordinated attacks by explosive-laden cars against a key military base in eastern outskirts of Mukalla, killing about 16 soldiers.

Over the past few weeks, Yemeni government forces and the Saudi-led coalition have been conducting well-planned and unprecedented attacks on key bastions of the al-Qaida terrorist group in the country's southern and eastern regions.

Hundreds of Yemeni soldiers newly trained by the Saudi-led coalition and supported by United Arab Emirates's special troops managed to recapture the coastal city of Mukalla in April after intense fighting and air raids on al-Qaida positions.

Yemen, an impoverished Arab country, has been gripped by one of the most active regional al-Qaida insurgencies in the Middle East.

The Yemen-based al-Qaida offshoot, also known as Ansar al-Sharia, emerged in January 2009. It had claimed responsibility for a number of attacks on Yemen's army and government institutions.

It took advantage of the current security vacuum and the ongoing civil war to expand its influence in Yemen's southern regions.

The fragile security situation in Yemen has deteriorated since March 2015, when a war broke out between the Shiite Houthi group, supported by former President Ali Abdullash Saleh, and the government backed by a Saudi-led coalition.

More than 6,000 people have been killed in ground battles and airstrikes since then, half of them civilians.