Two sisters killed as they crossed a road have been named.
Lily and Shelly Xin Wu, who were seven and six, were with their 39-year-old mother, 13-year-old brother and 12-year-old sister at around midday on Sunday when they were struck by a grey coloured Seat Leon.
West Midlands Police said the driver of the car, a 34-year-old Birmingham man, was arrested on suspicion of causing death by dangerous driving. He was released on police bail following questioning.
Sergeant Steve Newbury, from the force's Collision Investigation Unit, is leading the continuing investigation into the sisters' death. He said: "This tragedy has rocked the local community and devastated a family. Our thoughts remain with them.
"Lily and Shelly's mum remains in a critical condition in hospital with serious head injuries. She is yet to learn about the death of her daughters.
"The girls' brother and sister are still recovering in hospital and are being supported by family and friends. Their condition is described as comfortable and their injuries are not life-threatening.
"I would like to thank those who cared for the family as they lay injured. The courage the public displayed is commendable as were the actions of the emergency service staff who attended the devastating scene.
"In addition I would like to praise the way in which the staff at the children's schools have rallied round the family. They are also providing vital support to the children's friends who have been left badly shocked."