An Iowa woman was arrested on Monday for the 1983 double homicide of her estranged husband and his girlfriend, Fox News reported.

Theresa Lynn Supino, 53, was taken into custody at her Altoona home and charged with two counts of first-degree murder on the 31st anniversary of the deaths.

Supino allegedly killed 20-year-old Steven Fisher, whom she was separated from at the time of his death, and Fisher's 17-year-old girlfriend, Melisa Gregory.

An employee at the Copper Dollar Ranch, where Fisher worked, found Fisher and Gregory's bodies. According to an autopsy report, both died from massive head injuries.

Jasper County Sheriff John Halferty issued a statement following the break in the case that led to Supino's arrest.

"In the 31 years since the deaths of Steven and Melisa, the deputies, officers, agents, criminalists and many others have remained dedicated to assuring this case was never forgotten," he said.

However, Halferty did not specify what exactly led to the arrest and urged anyone with information on the case to contact police. He also said he decided to look into the unsolved case in 2003 and knew Gregory from junior high school.

"I was new to junior high and I just remember how friendly she was to me," the sheriff said at a vigil last year. "I live with that memory, and I'm in a position now where I think it is time. There are people locally that can help us with this case, and we're asking you to come forward and talk to us."

Supino is being held at the Jasper County Jail on $400,000 bond. She does not have an attorney yet and will appear in court for a preliminary hearing next week.

"It's been 30 years, 30 years way too long, to not know, to not have anybody convicted of this," Karen Gregory, wife of Melisa's brother, Scott, told the Newton Daily News. "It's time. It's time for not only families to be able to heal but the community as a whole to heal."