African Union forces along with Somali government troops on Tuesday took full control of the port city of Kismayo in southern Somalia.
Kismayo was the last stronghold of Islamist militants Al Shabaab. The Al Qaeda-linked group abandoned the city on the weekend.
Major Emmanuel Chirchir, a Kenyan military spokesman, posted on Twitter that once the new airport has been secured, it will be used for military landings.
According to the BBC, people in Kismayo said the Somali national flag had been hoisted by the army over the governor's office.
Military checkpoints have been set up in the city, and soldiers are patrolling, the BBC said.
The Associated Press reported that remnants of the Al Shabaab militants executed seven civilians who did not support them in the southern part of Kismayo on Monday, according to the Kenyan military.
Kismayo had been an important source of funding for the group since it was forced out of Mogadishu in August 2011.
Al Shabaab had used Kismayo's port to bring in weapons. The group had funded itself largely by charging taxes on goods arriving at the port.
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