One local aid worker in the small town of El Wak said the attackers hurled a grenade and then fired a rocket at a Kenyan police post.

Sheikh Hassan Hussein, the Chairman of the neighboring Gedo region in Somalia, said he was not sure of abductor's whereabouts.

Armed Somali groups have carried out scores of kidnappings in recent months, often targeting either foreigners or Somalis working with international organizations to demand ransoms.