CANBERRA  - A landslide swept through two villages in Papua New Guinea on Tuesday, covering much of the settlements in mud and leaving up to 40 people missing, officials and residents told Australian media. The accident, which occurred in the island state's Southern Highlands on Tuesday morning, prompted US oil giant Exxon Mobil to stop work at its nearby $15.7 billion liquefied natural gas (PNG LNG) project. The Australian Broadcasting Corporation said it was unclear how many people had been affected by the landslide due to conflicting local reports.