Alabama executes death-row prisoner with nitrogen gas

Alan Miller, 59, second person in US to be executed via controversial technique, shook and trembled on gurney

Alabama has carried out the second execution in the US using the controversial method of nitrogen gas, an experimental technique for humans that veterinarians have deemed unacceptable in the US and Europe for the euthanasia of most animals.

Alan Eugene Miller, 59, was pronounced dead at 6.38pm local time at a south Alabama prison.