Sixteen Muslim insurgents were killed in a predawn raid on Wednesday at a military base in northern Thailand, the deadliest toll the guerrillas have suffered in nine years. Around 60 militants tried to enter the base but were stopped by gunfire from marines, who had been tipped off about their arrival. Thailand’s military said the marines suffered no casualties. While violence is common in the north, the attack of the southern base indicates an escalation of the Muslim insurgency in the Buddhist-controlled country. Wednesday’s death toll is the largest since the military stormed a mosque in 2004, killing 32.