A mild earthquake measuring 3.9 on the Richter scale struck Himachal Pradesh's Shimla district on Wednesday night at a depth of 10 km. Tremors were felt in Jubbal and Rohru areas, but no loss of life or property damage was reported. Shimla: An earthquake of magnitude 3.9 struck Himachal Pradesh's Shimla district on Wednesday night, with tremors felt in Jubbal and Rohru areas.