Somalia's government spokesman said some 500 al-Shabab fighters have left the group and joined the government in a sign of disarray among the Islamist group's ranks, AP reported. Abdirahman Omar Osman said late Thursday that defections have been increasing since African Union and Somali troops captured the militant-held town of Afgoye outside Mogadishu last month. Abshir Ali Mohamed left al-Shabab this month. He believes the conservative militant movement will soon end. He said the group is suffering heavy losses. African forces have been battling al-Shabab on three sides for the last several months. Kenyan forces are expected to attack the al-Shabab-held port town of Kismayo in coming weeks. Kismayo is the last major stronghold al-Shabab still controls. Kenyan Prime Minister Raila Odinga promised this week that Kenyan troops would take Kismayo by August.