A major investigation, involving detectives from both British Transport Police and West Midlands Police, is now under way to try to identify both attackers and appeal for witnesses.
The first attacker is described as Asian with light skin, brown eyes, was of a skinny build and about 6ft tall. He was wearing a track suit top and bottoms, black trainers and was in his early 20s.
The second attacker is also described as Asian, in his early 20s, 5ft 6/7ins tall, of large build with a tight-cropped beard and was wearing a blue jumper and black jeans.
Detective Chief Inspector Tony Fitzpatrick, of British Transport Police, said: "This was a horrifying ordeal for this young girl and we have specially trained officers supporting her.
"It is now vitally important we investigate exactly what happened on Tuesday morning as well as identifying offenders for both of these awful incidents.
"My detectives are currently examining all available CCTV in an effort to identify the offenders and whilst these enquiries are made, we are keen to speak with any potential witnesses.
"Whilst this incident happened during the early morning and there may not have been many people around, I would be keen to speak with anyone who may have been in the area at the time.
"If you were passing by the station and saw two girls walking with an older man, then please get in touch immediately. Likewise, if you saw any suspicious vehicles close to Witton station close to 2am then please get in touch as soon as possible."
Fitzpatrick added: "We are now doing all we can to trace the people responsible and bring them to justice."
This article originally appeared on the Daily Telegraph
