Florida has executed a man known as the “ninja killer” for the 1989 slayings of a couple visiting the state from New Jersey.

The Florida Supreme Court on Thursday rejected arguments aimed at sparing the life of death row inmate Louis Gaskin, setting the stage for his execution next week in the 1989 murders of a Flagler County couple.

According to Attorney General Ashley Moody, Barwick was found guilty of first-degree murder in November 1986 for the death of Rebecca Wendt earlier that year.