The trial court denied without hearing appellant’s motion for relief under 28 U.S.C. § 2255 from a 10-year sentence imposed on his plea of guilty to a charge of assault with intent to murder. At the time of the commission of the crime appellant- was an inmate of the United States penitentiary at Leavenworth, Kansas. One of the grounds asserted for relief is mental incompetence at the time of a guilty plea. When such a claim is raised the § 2255 motion may not be disposed of without a hearing. See Nipp v. United States, 10 Cir., 324 F.2d 711, and Ellison v. United States, 10 Cir.,. 324 F.2d 710, and cases therein cited.

Reversed and remanded with directions to grant appellant a hearing.