Kenya's military said operation destroyed the training camp along with at least 4 improvised fighting vehicles and a weapons store. Al Jazeera

Kenya's military said its air force has attacked an Al-Shabab training camp in Somalia in retaliation for last month's mall siege that left at least 67 people dead.

The Kenya Defense Forces (KDF) said Thursday that they destroyed a training camp used by the members of the armed group, which claimed responsibility for the Westgate Mall attack on Sept. 21.

"This was part of a broader mission by the AMISOM, the U.N.-backed African peacekeeping mission in Somalia, targeting where the Shabab were training. Those attackers at the Westgate did their training there," Col. Cyrus Oguna, a spokesman for the Kenyan military, said.

"We have been monitoring this particular area over a period of time, and we moved in when we got the green light." The camp had over 300 fighters, many of whom are believed to have been killed or injured, the KDF said in a statement (PDF).

Kenya's military said the "major aerial offensive" in the Dinsoor region completely destroyed the training camp along with at least four improvised fighting vehicles and a weapons store.

However, Al-Shabab denied there had been any attack.

"No military camp of ours in Somalia was air struck or attacked," the group’s senior media officer told Reuters, adding that its fighters had attacked Badhaadhe town in the south.

A U.S. drone strike on Monday, meanwhile, killed two leading members of Al-Shabab. Oguna said raids on the armed group's strongholds would be sustained.

Al Jazeera and Reuters