Somalia's al-Shabab says it has 'executed' five suspected spies
The militants announced the killings on its Andalus radio station, saying they were carried out in a public square in Jilib town in Middle Jubba region late on Tuesday.
According to residents, the men were tied to poles and shot by a firing squad shortly after a self-proclaimed judge sentenced them to death.
Al-Shabab, al-Qaeda's East Africa affiliate, has fought for years to impose a strict version of Islam in the Horn of Africa nation.
Despite losing territory in recent years, the extremist group continues to carry out deadly attacks in many parts of the country, especially the capital, Mogadishu. A truck bombing there in October 2017 killed 512 people.
Experts describe the bloated and largely ineffective Somali army as a collection of clan militias, with various international militaries providing poorly-coordinated training to different units.
Despite losing towns and territory in recent years the group continues to carry out regular bombings and armed raids on government, security and civilian targets in the capital and elsewhere.