A tank advances towards the town of Tal Ksaiba, near the town of al-Alam, March 7, 2015. Iraqi security forces and Shi'ite militia fighters struggled to advance on Saturday into the two towns of al-Alam and al-Dour near Tikrit, their progress slowed by fierce defence from Islamic State militants. REUTERS/Thaier Al-Sudani (IRAQ - Tags: POLITICS CIVIL UNREST CONFLICT)