The Vanchiyoor police arrested an accused in a case who stabbed a witness in the same case inside the Vanchiyoor court premises on Monday afternoon. The arrested has been identified as Vimal Jose, a native of Pattoor, an accused in the case related to an assault registered in 2014. He had allegedly stabbed Ernakulam native Nithin. The victim has been admitted to the Government Medical College Hospital here with injuries.