Thirty-seven guards of a Turkish prison were assigned to different cities on Thursday, after 18 inmates broke out of the prison last week, local NTV news channel reported. The 18 inmates, convicted of joining the outlawed Kurdish Workers\' Party (PKK) as well as aiding and abetting lawbreakers, escaped from the Bingol M-type Prison in the eastern province of Bingol on Sept. 25 through a tunnel they dug. Among them, 17 were caught in a rural area near Ortacanak village of Bingol province; another one remains on the run. Turkish authorities have been investigating whether there was any negligence or assistance inside or outside the prison, Interior Minister Muammer Guler said. The PKK, listed as a terrorist organization by Turkey and part of the international community, took up arms in 1984 in an attempt to create an ethnic homeland in southeastern Turkey. Since then, over 40,000 people have been killed in conflicts involving the group.