Somali militant group al-Shabab has claimed responsibility for Tuesday's bombing and assault of a government complex in the capital, Mogadishu.

Security Ministry spokesman Mohamed Yusuf told VOA Somali that 18 people were killed and at least 15 others wounded in the attack on the country's Higher Education Ministry.

A witness said militants set off a car bomb outside the ministry walls, allowing the attackers to storm the building and open fire.

The gunmen took control of two floors of the building, but were pushed out by Somali security forces and African Union troops after a fierce gunbattle.

Somali officials say eight civilians were killed during the incident, along with seven attackers, two Somali security force members and one African Union soldier.

The building that was attacked also houses the Petroleum and Minerals Ministry.

The attack was similar to other bomb-and-gun attacks carried out by al-Shabab, which is attempting to overthrow the Somali government and establish an Islamic state.

Earlier this month, al-Shabab staged an attack on Kenya's Garissa University College, killing 148 people. Al-Shabab said that attack was revenge for Kenyan military action inside neighboring Somalia.

Somalia's government has placed bounties on the heads of 11 al-Shabab leaders, including the militant group's top leader and the alleged mastermind of the massacre in Kenya, Mohamed Mohamud, also known as Dulyadin.

The bounties, announced last Thursday, include a reward of $250,000 for the capture of al-Shabab chief Ahmed Omar Abu Ubyed and amounts of between $100,000 and $150,000 for 10 other prominent militants.