An Illinois man has been arrested for murder days after his parents were reported missing, authorities announced saying they are still trying to find the bodies.

Jose Ramirez, 21, was arrested Monday and charged with first-degree murder in connection to the deaths of his mother Susan B. Brill De Ramirez and his father Antonio Ramirez Barron.

The couple both worked at Bradley University in Peoria. Brill De Ramirez was an English professor, and her husband worked as a technology support specialist.

Another man, 21-year-old Matthew Roberts, was arrested and charged with concealment of a homicidal death and obstruction of justice.

The couple, both 63, have been missing since Thursday.

Jose Guadalupe Ramirez, left, and Matthew James Roberts. Peoria County Sheriff's Office

The Peoria County Sheriff's Department said in a news conference that a family member called deputies to the Princeville home Sunday around 10 p.m. CT (11 p.m. ET) for a suspected burglary. When deputies arrived, they found blood in the home, sheriff Brian Asbell said.

Brill De Ramirez and Barron were not at the house sparking a search for the couple. The sheriff's department released a statement on Facebook Monday night announcing that an arrest was made and Brill De Ramirez and Barron are deceased.

Authorities have not released details on what led to the arrests, but Asbell said they were based on a confession, NBC-affiliate KXAS-TV reports.

Deputies believe the bodies are somewhere in Henry County but have not yet located them. Asbell said he believes Brill De Ramirez and Barron were killed Friday morning.