West Midlands police are hunting two men after a 34-year-old man is cut with a knife, held down and raped in Chelmsley Wood.
The victim is said to be traumatised after being confronted by two men with a knife and slashed across the back.
Detectives are urging witnesses who saw anything suspicious in the area of Longley Walk, near Keepers Lodge, at about 2125 BST on 23 July, to come forward.
A police spokesman said: "One of the men held the victim down while the other raped him.
"The offenders then ran off in an unknown direction."
Both attackers are white and in their late 20s. One has a Belfast accent.
Detective Constable Ian Bode, of Solihull north CID, said: "The victim is distressed and traumatised by the whole incident and we are anxious to trace the offenders."