Image copyright Reuters Image caption Some of those injured in the blast are said to have suffered severe burns

One person has been killed and several others injured in an explosion at a hospital in the US state of Texas, officials say.

The blast occurred at about 14:30 local time (19:30 GMT) on Tuesday in an area under construction at the facility in the city of Gatesville.

One eyewitness said an electrical generator had blown up at the site.

The hospital and nearby nursing homes were evacuated and power was reportedly lost in some areas of Gatesville.

Images and footage of the incident shared on social media showed black smoke billowing from the grounds of Coryell Memorial Hospital.

Image copyright Reuters Image caption Footage showed emergency services rushing to the scene

Initial reports suggested that the blast occurred in an area on the hospital grounds where a new wing was being built. Investigators are said to be looking at a boiler room that was under construction.

The Coryell County emergency management co-ordinator, Bob Harrell, said some of those injured had suffered severe burns and were taken to the Parkland Memorial Hospital in Dallas, the Associated Press news agency reported.

Search dogs will examine the wreckage of the wing despite all workers being accounted for, Mr Harrell added.