Characteristics of compact intracloud discharges observed in a severe thunderstorm in northern part of China

► We located a total of 236 Compact intracloud discharges (CIDs) in three dimensions or two dimensions. ► We approved that CID exhibit isolated or as the initial breakdowns of lightning discharges. ► We also found many CIDs being embedded in ordinary lightning discharges. ► We have performed a statistical study on their parameters. ► We discussed the activity characteristic of CIDs.