"The second vehicle, a black cab, was on its side".
A West Midlands Ambulance Service spokesman said a man and a woman in the first auto were taken to Heartlands Hospital for treatment to "relatively minor injuries". Sadly, he died at hospital'.
"Sadly, there was nothing that could be done to save the driver and he was confirmed dead at the scene", the spokesperson said.
Two passengers in the back, a man and a woman, were quickly removed by the emergency services.
The Hazardous Area Response Team of West Midlands Ambulance Service have described it as a "significant incident", while witnesses said the tragedy just days ahead of Christmas was the "worst thing they had ever seen".
Police tweeted that this was a "very serious incident", and that the scene was "very hard and upsetting", asking witnesses to contact them. Three of them were declared dead at the scene.
"The first West Midlands Fire Service crews arrived in less than four minutes and were met with a complex scene, spread over some distance", Area Commander Jason Campbell said.
'Unfortunately, it was not possible to save the woman and she was also confirmed dead at the scene.
Three other cars collided as they tried to avoid the crash, which happened at 1.10am today at the entrance to an underpass on Lee Bank Middleway, at the junction of Bristol Road, near Edgbaston.
"The man was taken on blue lights to the major trauma centre at the Queen Elizabeth Hospital Birmingham with the MERIT trauma doctor travelling with the crew".
The fourth was taken to the major trauma centre at the Queen Elizabeth Hospital Birmingham in a critical condition.
In the first auto, there were a man and a woman.
She said: 'I was in the McDonald's drive through and there were two loud bangs.
'Other cars behind had bumped into each other, probably from slamming their brakes on.
Police officers dealing with the horrific incident described it as "very hard and upsetting".
"There was another small vehicle further down that had been crashed into, but yes there was the taxi and the auto up against the wall". It didn't look good at all.
"I hope everyone involved is okay, especially this close to Christmas".