A man holding a large American flag, carrying a gun, was at the scene of the Sante Fe High School shooting in Texas and said “Make America Great Again”.

He was speaking to local KHOU-TV reporters near the scene where Texas governor Greg Abbott said ten people have died, which ten others were injured. The man said he was there to “offer support” but it was unclear what kind of support he was offering by echoing US President Donald Trump’s now-famous slogan.

“‘God bless ya’ll’ will go a long way...right now,” the man said before walking away when it was clear he was openly carrying a pistol on his right hip, clipped to his shorts. An unidentified then appeared on camera, chastising the first man.

Standing near a petrol station, the second man said to reporters "that's not what America needs. America needs prayers," adding that though he supports Second Amendment rights to carry firearms, he thought it was "an embarrassment" that the flag-carrier showed up at the high school "crime scene" while openly carrying a gun.

He said he hoped "they would get him," perhaps implying he hoped police would arrest him. "This idiot is walking down the street with a damn pistol on the site where we just had kids get shot," the second man said.

"I have guns...but this idiot is walking down here saying 'Make America Great Again,' that's not what America needs. America needs prayers, we don't need this crap," he said animatedly.

Santa Fe High School shooting

Harris County Sheriff Ed Gonzalez said the majority of the fatalities are students. At least eight students were treated for gunshot wounds, six of whom have been released from hospital. At least one patient is still in fair condition and expected to remain in hospital for several days and three more are being treated in area hospitals.

At least one police officer, John Barnes, was also injured and remains in critical condition. Mr Barnes had retired from the Houston police force before joining school staff.

Police identified a suspect, 17-year-old student Dimitrios Pagourtzis, and he is in custody. One other person has been detained but not identified, Mr Abbott said, adding that police are questioning the person.

The governor also confirmed during a news conference at the scene that the explosive devices found in the wake of the shooting included a molotov cocktail that had been found in the suspected shooter's home and a vehicle parked near the school. CNN has reported that police are investigating two homes approximately three to four miles away from the school, in the Houston suburb.