Aceh, Indonesia's most western province, lost 100,000 people or 25% of it's whole population in the 26th December 2004 tsunami, out of a death toll of almost 300,000 people from 42 different countries. Worst hit was Indonesia with 220,000 victims and near the epicentre, the 30-35ft (10-12m) waves left waterlines up to 60ft (20m) above sea level. Aceh boasts 1,500km (932mi) of coastline and more than half of it was hit by the tsunami. Sumatra is the fifth largest island in the world and the third largest in Indonesia. The Aceh province has historically been more Muslim than other regions of Indonesia, but when Indonesian president Suharto pressured Aceh to come closer to the centre, it sparked off the Free Aceh Movement (GAM), which meant assassinations, torture and alienation to the general population. The guerrilla war continued through the 1990s, with an estimated 15,000 casualties on both sides, before an army offensive from 2002 - 2004 killed half of the GAM forces.