A car has crashed into a hospital emergency room in Texas killing the driver and injuring five others.

The sedan smashed into the lobby at St David’s North Austin Medical Centre shortly after 5.30pm on Tuesday.

The driver was pulled from the car but could not be revived and died at the scene, authorities said.

Stephen Hughes said he was at the hospital waiting for his wife to come out of surgery when he heard a loud bang, according to CNN.

“At first I thought it was an explosion,” he said. “Then I heard screaming and saw the smoke coming from the ER entrance.”

Police have launched an investigation but officers said preliminary inquiries indicate it was not an intentional act and there was “no threat to the general public”.

Captain Christa Stedman of Austin-Travis County Emergency Medical Services said a child who was hit by the car is in a critical condition while an adult sustained “serious, potentially life-threatening injuries”.

They were taken to different hospitals along with two other people who were hurt in the incident. Another was treated at the emergency department at St David’s.

Dr Peter DeYoung, chief medical officer for the hospital, said eight patients who were already undergoing treatment at the ER were moved to other facilities.

He said the emergency department doors were damaged along with an aquarium in the lobby. 

Ambulances were diverted to other hospitals but the emergency department was still taking walk-ins who would be treated at a makeshift triage area, he added.

“We’re hoping to kind of regroup here over the night and see where tomorrow leaves us,” Mr DeYoung said.