Saadaq Omar Hassan, who was in charge of police operations in Somalia's capital, said he was acting unilaterally to prevent MPs from extending the term of President Mohamed Abdullahi Mohamed.

"We have stopped the parliament session today. We have a responsibility bigger than a personal one," Hassan told local television station Universal in a live speech.

"We have to solve anything that can bring violence and war in Mogadishu.

"The four-year term has ended."

Moments later, Somalia's police commissioner Hassan Mohamed Hijar announced on Facebook that Hassan had been fired and replaced.

The chaos underscores the widening divisions within the Horn of Africa's security services over extending the four-year term of President Mohamed, who faces growing pressure to quit after his term as national leader ended in February.

Australian Associated Press