A Somali official confirmed reports of an attack on a U.S. base in the country on Monday. Yusuf Abdourahman, a security official with the Lower Shabelle regional administration, told The Associated Press that a suicide car bomber detonated a vehicle packed with explosives at the gate of a military airstrip that serves as a base for U.S. and Somali forces.

He said a burst of gunfire could be heard across the base after the bombing, suggesting an ongoing attack on the facility.

Somalia's Islamic extremist rebels, al-Shabab, claimed responsibility for the attack.

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The U.S. military uses Belidogle airstrip in the Lower Shabelle region as a base where it launches drones that attack al-Shabab and trains Somali troops. AFRICOM confirmed a strike by U.S. drones about two weeks ago in support of Somali forces who came under attack by al-Shabab militants while on patrol in Lower Juba province.

There was no information immediately provided by the U.S. military's Africa Command (AFRICOM) on the incident at Belidogle.

Al-Shabab, which often exaggerates its battlefield operations, claimed in a statement posted online that the attack began with multiple explosives-laden trucks, which it said had allowed a group of militants to get into the base where they "engaged American troops."

There were reports of a second attack on European Union peacekeepers in Somalia's capital, Mogadishu. A Reuters journalist reported seeing a seriously damaged armored vehicle with a small Italian flag on it after an explosion that apparently targeted an EU convoy. There were no immediate reports of casualties.

Al-Shabab was behind the brazen assault on a shopping and hotel complex in Nairobi, Kenya, in January that left more than 20 people dead, including one American man.

Kenyan intelligence officials told CBS News that the al-Shabab cell in Kenya behind that attack had been scouting the upmarket dusitD2 hotel complex for at least two years.