Yemeni interior ministry issued directions on Saturday to police departments in the capital's secretariat and all governorates in the country to tighten security measures in prisons.These measures came after a prison break that took place last Thursday at Sanaa central prison, in order to prevent any security breach and smuggling of prisoners, ministry said in a press statement. The ministry stressed importance of boosting security vigilance and dealing firmly and strongly with crimes that target prisons. Last Thursday, 29 prisoners, including 19 linked to Al-Qaeda, escaped from Sanaa central prison during an attack that led to killing nine guards.