The 39-year-old Sri Lankan national (pictured) was found collapsed in the Bordesley Street car park by a security guard at around 9.15am on 28 February having travelled up from London by coach the previous night.
Emergency services attended but nothing could be done to save the man and he was pronounced dead at the scene.
Detective Sergeant Mick Perkins, from the West Midlands Police Homicide Team of Force CID, said: “Initially the man’s death was treated as natural causes…however a post mortem examination suggested otherwise and a full inquiry has now been launched.
“We now know that the man had multiple injuries to his chest and pelvis but how he came by these injuries remains a mystery.
“The man got off a coach at the city’s main coach station in Digbeth and walked towards Bordesley Street at around 10.15pm on Friday 27 February. We need to speak to anyone who may have seen him on this journey and can help us piece together his last movements or saw him in or near the Bordesley Street car park that night. We also need to understand why he came to Birmingham so I’d urge anyone with information to call me.”
The man had been living in Southall, London, prior to travelling to The Midlands. The purpose of his journey is unknown and police have failed to locate any relatives living in the UK although family in Sri Lanka have been informed.
His is described as a Sri Lankan man, 39-years-old, around 5ft 9in tall, of slim build, with a dark beard and he was dressed in a black coat and blue jeans.
If you have any information please contact Detective Sergeant Mick Perkins on the Homicide Team at Harborne Police Station on 101 or call Crimestoppers anonymously on 0800 555 111.