Two cars were involved in the collision on New John Street West, one of the main roads through central Birmingham, just before 4am on Saturday.
A 20-year-old man has been arrested on suspicion of causing serious injury by dangerous driving.
He remained in custody on Saturday lunchtime while the two injured men were being treated in hospital for critical injuries.
UPDATE: Man dies after crash
Meanwhile New John Street West, the A4540, stayed cordoned off at the junction with Summer Lane next to the Texaco garage as collision investigators examined the scene.
The silver Mercedes and blue BMW involved in the crash were both left with substantial front-end damage, while barriers next to the road were knocked over.
Police have urged anyone else who was involved in the collision to come forward.
A West Midlands Police spokesman said: "We believe others from both cars may have left the scene and we are asking them to come forward so that we can understand what happened.
"Anyone with information or footage of the incident should also contact us via live chat on our website or by calling 101 quoting log 558 of 31/7.
"You can also email the Serious Collision Investigation Unit on firstname.lastname@example.org."