A US woman has been charged with murder after shooting an Uber driver she thought was kidnapping her, police say.

According to police in the border city of El Paso, Texas, Phoebe Copas believed she was being taken into Mexico.

She then shot driver Daniel Piedra Garcia, the authorities said in a statement.

The 52-year-old died in hospital after several days on life support.

As she was in the car, Copas saw traffic signs that read Juarez, Mexico, according to police documents.

The two cities lie side-by-side on either side of the US-Mexico border.

Police documents further explain that after thinking she was being kidnapped, Copas pulled a gun from her handbag and shot the driver in the head. The car then hit barriers before coming to a stop.

Copas - who is from Kentucky but was visiting her boyfriend - is alleged to have then called the emergency number 911, took a photo of the driver and texted it to her boyfriend.

"The investigation does not support that a kidnapping took place or that Piedra was veering from Copas' destination," El Paso police statement said.