Can a prison official be held liable for an assault committed by an inmate at the hands of another inmate?

prisoner at the hands of another . . . translates into constitutional liability for prison officials responsible for the victim's safety." Id. at 834. A prison official may be held liable for an assault suffered by one inmate at the hands of another only where the assaulted inmate can show that the injury is sufficiently serious, id. at 834 (citing Wilson v. Seiter, 501 U.S. 294, 298 (1991)), and that the prison official was deliberately indifferent to the risk of harm, id. at 837. That is, the defendant must have known that the inmate faced a substantial risk of serious harm, and must have also disregarded that risk by failing to take reasonable measures to abate it. Farmer, 511 U.S. at 847.

Should plaintiff choose to file an amended complaint, the amended complaint shall clearly set forth the claims and allegations against each defendant. It must also allege a cognizable legal theory against a proper defendant and sufficient facts in support of that cognizable legal theory. Lopez v. Smith, 203 F.3d 1122, 1126-27 (9th Cir. 2000) (en banc) (district courts must afford pro se litigants an opportunity to amend to correct any deficiency in their complaints).