NAIROBI: A Kenyan police official says members of an extremist group attacked a police convoy escorting goods and shot dead two people, including a police officer, in the coastal Lamu County. Police spokesman Charles Owino said Thursday al-Shabab militants attacked the convoy on the Mpeketoni-Lamu road late Wednesday burning vehicles and driving another police vehicle to Somalia. This is the third attack by Somalia's al-Shabab rebels since Sunday targeting Kenya security forces along the Somalia border. One soldier died and another was wounded Sunday when al-Shabab attacked a military car in the northern Mandera town. Five police were wounded Tuesday by a roadside bomb in Mandera. Kenya has experienced a wave of retaliatory attacks by al-Qiada-linked al-Shabab since it sent its troops to Somalia to fight the extremists in 2011.