An unarmed Czech police officer killed two men who attacked him in Liberia, Mladá fronta Dnes reported. A week ago the elite police officer, who is serving in a United Nations peace mission in the East African state, stopped his car to help a man who appeared to be in distress. He was then set upon by a group of men wielding machetes. He killed two of them in self-defence before making his escape, a police spokesperson told the newspaper. The Czech policeman, a martial arts expert, suffered cuts during the attack. Five Czech police officers are taking part in a UN mission aimed at increasing stability in Liberia.