MEIKHTILA, Myanmar — The top UN envoy to Myanmar yesterday toured a city wracked by the country’s worst Buddhist-Muslim violence this year, calling on the government to punish those responsible for a tragedy that left dozens of corpses in the streets, some charred beyond recognition.

Vijay Nambiar, the UN secretary-general’s special adviser on Myanmar, also visited some of the nearly 10,000 people driven from their homes after sectarian unrest shook the city of Meikhtila for several days this week.