Police responding to a domestic incident at the Sirhowy Arms Hotel in Argoed, Blackwood at 1.23am on Thursday 6th November following reports a man was attacking a woman.
When officers from Gwent Police arrived the male continued attacking the female, police deployed Taser and the male was subsequently arrested.
The female suffered serious injuries and was pronounced dead at the scene.
The male whilst under arrest became unresponsive. officers and paramedics administered first aid, he was pronounced dead a short time later.
Police have referred the matter to the IPCC and are not looking for anyone else in connection to the incident.