Meanwhile, Setthathirath's forces sacked the Burmese garrison at Vientiane. Fortunately for the Burmese, so it seemed, the Lan Xang king was killed shortly after—sometime before mid-1572, and a senior minister and general named Sen Soulintha seized the throne. (In Laotian history, the events took place a year earlier. Setthathirath retook Vientiane in the dry season of 1570–1571, and died in 1571.) Much to his surprise, Soulintha refused Bayinnaung's ultimatum to submit. Incredulous, Bayinnaung sent Binnya Dala to lead an invasion with a small army of 6000, with the majority of troops coming from Lan Na and Siam. But he and the Toungoo court had underestimated the opposition. Lan Xang's strength was more than Setthathirath, and Soulintha proved no pushover. The small Burmese army suffered from guerrilla attacks, and had to retreat in early 1573. At Pegu, the king was furious at Binnya Dala, hitherto his most trusted adviser and favorite general, despite the fact that he had given the general little to work with. He sent Binnya Dala into exile "to a sickly place" in central Siam, where the general who had won him many a battle died from illness six months later.