A US prisoner who killed his former girlfriend decades ago has been executed despite pleas from the victim’s family to spare his life.

Joe Nathan James Jr received a lethal injection at a south Alabama jail after the US Supreme Court refused his request for a stay of execution.

James was convicted of murder and sentenced to death after Faith Hall, 26, was shot dead in 1994, in the city of Birmingham.

Ms Hall’s two daughters, who were three and six when their mother was killed, said they wanted the 50-year-old to serve life in prison instead of being executed.

Prosecutors said James briefly dated Ms Hall and became obsessed with her when she rejected him.

He stalked and harassed her for months before killing her.

On 15 August 1994, Ms Hall was at a friend’s house when he forced his way into the apartment, pulled a gun from his waistband and shot her three times, according to court documents.

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Ms Hall’s family, who did not attend the execution, said it was a “tragic day” for them.

“We are having to relive the hurt that this caused us many years ago,” they said in a statement.

“We hoped the state wouldn’t take a life simply because a life was taken and we have forgiven Mr Joe Nathan James Jr for his atrocities toward our family.

“We pray that God allows us to find healing after today and that one day our criminal justice system will listen to the cries of families like ours even if it goes against what the state wishes.”

Alabama Governor Kay Ivey said she always deeply considers the feelings of the victim’s family and loved ones, but “must always fulfil our responsibility to the law, to public safety and to justice”.

“Faith Hall, the victim of repetitive harassment, serious threats and ultimately, cold-blooded murder, was taken from this earth far too soon at the hands of Joe Nathan James Jr,” she said.

“Now, after two convictions, a unanimous jury decision and nearly three decades on death row, Mr James has been executed for capital murder, and justice has been served for Faith Hall.”

She said the execution meant an “unmistakable message was sent that Alabama stands with victims of domestic violence”.