Four more Christians have been executed by radical Islamists in Somalia.

The human rights agency International Christian Concern reports members of the al-Shabab extremist group kidnapped and beheaded the believers late last month.

The four worked for an organization helping orphans in southern Somalia.

A spokesman for al-Shabab said the workers were guilty of abandoning Islam.

An eyewitness told ICC  the four Christians were given the chance to renounce their faith in Jesus Christ and to embrace Islam.

They refused, even though the terrorists promised to release them.

Al-Shabab has been waging war against the tiny Christian population in Somalia.

It's seeking to overthrow the government and establish an Islamic state.