Kenya has blamed previous abductions of tourists and aid workers on Al-Shabaab . NEW : A shootout frees the four aid workers , the Kenyan military says . The U.S. State Department said it was "deeply concerned" about reports of civilian casualties in Kenya and called for an investigation. The abductors get away with a refugee council vehicle . Kenya has blamed previous abductions on the militant Al-Shabaab group .
NEW : A shootout frees the four aid workers , the Kenyan military says . The U.S. State Department said it was "deeply concerned" about reports of civilian casualties in Kenya and called for an investigation. The abductors get away with a refugee council vehicle . Kenya has blamed previous abductions on the militant Al-Shabaab group .