Brad Sigmon, who admitted to killing his ex-girlfriend's parents, said he chose to die by bullets because he considered the other choices offered by the state to be worse.

"I want my closing statement to be one of love and a calling to my fellow Christians to help us end the death penalty," Brad Kieth Sigmon wrote ahead of his execution.

South Carolina executed a convicted murderer by firing squad on Friday, the first use of the method in the United States in 15 years.