A mother of six young children has been tragically killed when her bicycle was hit by a car at Munno Para.

Carolyn Riggs, 32, was just a few hundred metres from her Smithfield Plains home, where she lived with her long-term partner and their children, when the horrific collision happened on Curtis Rd near the Munno Para McDonalds about 8.45pm on Saturday.

The family was too heartbroken to speak publicly except to say that they “loved her to bits”, while other relatives shatteredat the news expressed their sorrow on social media.

The children are aged between three and 12.

The woman was heading to the McDonald’s when the tragedy took place on the intersection of Ramsar Rd, where she had triedto cross Curtis Rd.

Witnesses rushed to help the woman who was flung from her bicycle still wearing her helmet.

Local Tony Burnett said he came out of his house and saw people gathering around the cyclist who was lying on the ground unresponsive.

“It was horrible, she was in a bad way,” he said.

“We were told not to touch her, she still had her helmet on, we were told not to take it off until the ambulance arrived.”

Mr Burnett said he helped paramedics shined a torch as they desperately tried to save the woman.

“I was helping the ambos providing them assistance, unfortunately that wasn’t enough,” he said.

“There were 20, 30 people around just standing in disbelief.”

Mr Burnett said many accidents happened on the “dangerous” Curtis Rd.

Hayley Easthope, 25, was driving several cars behind the vehicle involved in the crash and immediately pulled over.

“We all just stood by her (the cyclist’s) side and I was telling everyone not to move her in case of injuries,” the aged careworker said.

“She was unresponsive, not moving at all when we got to her.

“She was unresponsive but we just kept comforting her, telling her it’s going to be OK.”

The cyclist was rushed to Royal Adelaide Hospital with serious injuries but died overnight.

Her death brings the state’s road fatalities to 90 compared to 61 the same time last year.