Mogadishu, Somalia - Somali rebel group al-Shabab has denied claims by the US defence department that more than 150 of its fighters were recently killed in air strikes.

Washington said on Monday that it had carried out several strikes in southern Somalia on the Raso training camp, in which it claimed more than 150 of the al-Qaeda-linked group's fighters died.

"The Americans are dreaming. We never gather that many of our fighters in one place. We know the security situation," Abdulaziz Abu Musab, the group's military operations spokesman, told Al Jazeera in a phone call on Tuesday.

"Yes, the attack happened and it happened at the location they mentioned, but the number they are telling the world is a lie," Musab added.

What does al-Shabab want?

The armed group, which is fighting Somalia's internationally recognised government, has recently attacked and overrun military bases belonging to the African Union peacekeeping mission, AMISOM.

The US air strikes occurred at 14:00 GMT on Saturday at a camp about 130km from Belidogle airport in the Lower Shabelle region - a major base for AMISOM troops. American soldiers are also present at the Belidogle base.

Pentagon spokesman Captain Jeff Davis said: "The fighters were there training and were training for a large-scale attack ... We know they were going to be departing the camp and they posed an imminent threat to US and [African Union] forces.

"It was an air operation. Initial assessments are that more than 150 terrorist fighters were eliminated."

Al-Shabab on January 15 attacked and captured an AMISOM base home to Kenyan troops in El Adde, southwestern Somalia. The group killed dozens of Kenyan troops and captured several soldiers.

The group also carried out a similar dawn raid on an African Union base in September 2015, killing 20 African Union soldiers.

They also overran a Ugandan army-run base in Janaale, about 90km southwest of the Somali capital.

In June 2015, the group captured another African Union base in Lego, killing dozens of soldiers and seizing weapons and ammunition.

The group has lost control of most towns and cities in the country but continues to carry out attacks. Al-Shabab was pushed out of Mogadishu in August 2011.

Follow Al Jazeera's Hamza Mohamed on Twitter: @Hamza_Africa