Ananova:

A man has been executed in the US for murders he committed 30 years ago.

Prosecutors once described the killing of six members of a farming family as the most gruesome in the state's history.

Carl Isaacs, 49, was given a lethal injection at the state prison in Jackson for the killings on May 14, 1973. Appeals kept him on death row longer than anyone else in the United States.

The US Supreme Court refused to grant a last-minute stay, although Justices John Paul Stevens and Stephen Breyer said the court should have agreed to consider Isaacs' claim that it was unconstitutional to execute him after his long imprisonment.

The murders prompted legislation that requires victims' families to be notified of developments in death penalty cases and inspired the movie Murder One.

Over the years, Isaacs' lawyers argued that publicity prevented him from receiving a fair trial and tried to explain his actions by shedding light on his abusive childhood.

Relatives of the murdered Alday family never wavered in their public push for Isaacs to be executed. The repeated delays angered them, and some relatives died waiting for the execution. Three members of the family were witnesses.

In his final days, Isaacs, through his lawyer, offered remorse for the killings, saying he was not the same hot-headed person who committed the crime at 19.

The Alday family was unmoved, citing Isaacs' own boastful words in a series of 1975 prison interviews.

"I'd like to get out and kill more of them," he said at the time. "They represent the type of society I don't like. I didn't know them, had never seen them before May 14, but I didn't like them. Working people don't do a damn thing for me."

The Aldays were shot to death as they returned home for lunch. Ned Alday was gunned down along with three sons, a brother and a daughter-in-law, who was raped and then taken to a field where she was shot in the head.

At the time of the murders, Isaacs was on the run after having escaped from a minimum-security prison camp in Maryland. Two other men are serving life sentences for the murders. A third was released from prison in 1993.

© Associated Press