Police are still hunting for two convicted murderers who escaped from a high security prison house in Plzen on Tuesday. The convicts escaped with the aid of a guard by hiding in a service truck. The head of the Plzen-Bory prison in western Bohemia has been sacked and Justice Minister Pavel Nemec has ordered a full investigation. Escaped convict Roman Cabrada is a drug dealer who was serving time for the murder of a German mayor two years ago. The other inmate, Rostislav Roztocil, had killed an Egyptian student. An e-mail from his sister in Germany suggests he may already have escaped from the Czech Republic.