Police are hunting for two suspects who killed a 24-year-old social worker outside the Alexandra Clinic in northern Johannesburg on Wednesday.

Bianca Walburton was shot as she drove out of the clinic by hijackers trying to steal her car.

She drove a few metres before dying behind the wheel.

Traumatised family members and friends gathered at the scene.

They struggled to hold their tears back as emergency workers removed her body and combed the scene for bullet cartridges.

The clinic's Gabrielle Ngwenya said patients and staff members were traumatised.

"We are going to give support to our staff. Those who need counseling will be given counseling because some are very shocked and traumatized by this incident," he said.

The suspects escaped on foot.

Wits University's Sherona Patel said the facility was mourning the loss of one of its master's students.

"On behalf of Wits University, we would like to extend our deepest sympathies to the friend and families of Miss Warburton."