The appellant, Praphull Kumar, filed a criminal appeal against the acquittal of respondents 2 to 5, who were accused of murdering his father, Suresh Thakur, and injuring several others. The trial court had found that the prosecution failed to prove its case beyond reasonable doubt. The appeal was filed under Section 372 of the Code of Criminal Procedure. The High Court of Judicature at Patna heard the appeal and considered the evidence presented. The court's decision is not specified in the provided text.