Two men have been praised for coming to the aid of a pregnant woman who was stabbed following the stabbing on Trinity Hill in Sutton Coldfield
A pregnant woman is in a critical condition in hospital after being stabbed in a town centre.
Passers-by flagged down police on Trinity Hill in Sutton Coldfield following the attack at about 15:15 GMT.
West Midlands Police said a 41-year-old man, who was known to the woman, was arrested at the scene.
Two men suffered minor hand injuries after intervening and have been receiving treatment in hospital.
A large area of the town centre has been cordoned off while police investigate the scene.
Julian Harper, incident manager for West Midlands Police, said officers were "working hard" to piece together the incidents before the assault, and praised the two men for intervening.
"[They] bravely stepped into what was a dangerous and volatile situation, with complete disregard for their own safety and I commend them for their actions," he said.
West Midlands Ambulance Service said the woman, 40, was airlifted to hospital.