BEIRUT, Lebanon — In a recent video from Saudi Arabia, three uniformed security officers and a professional swordsman in a white gown struggled to placate a woman cloaked in black and sitting in the street. A Saudi court had convicted her of murder, but she was proclaiming her innocence.

Then the officers stepped back, the swordsman took aim and the woman shrieked and fell silent as he struck her neck with his blade, three times in total. Medics wearing white gloves tended to the body, and the swordsman wiped his blade with a cloth.

The video was distributed by human rights activists and posted online after the execution in the city of Mecca on Jan. 12, shedding light on the way Saudi Arabia applies the death penalty.

On Sunday, Saudi news outlets reported that the authorities had arrested the man who had shot the video and planned to prosecute him. Although the reports did not specify what charges he faced, an Interior Ministry spokesman said such matters fell under the country’s law against cybercrimes.