why was a former chief justice detained?

Former Chief Justice Cholendra Shamsher Jabara Rana was detained at midnight and held for about 10 to 12 hours by police in Kathmandu. The detention happened without an arrest warrant and the official reasons were not clearly disclosed. However, some reports mention alleged security threats from Janajati groups as the justification for his overnight detention. After being held, he was released citing security reasons. This incident has raised questions about the legality and transparency of the detention.