Stephen Treon, the former husband of First Lady Jill Biden, has been charged with the murder of his wife, Antoinette Bruno Treon, Delaware State Police announced Tuesday. The charges stem from an “extensive weeks-long investigation” into Bruno Treon’s death.

Bruno Treon, 42, was found deceased at their home in Lewes, Delaware, on June 29, according to police. Initial reports indicated she died of a possible accidental overdose, but the investigation revealed suspicious circumstances leading to the murder charge against Treon.

Stephen Treon, 49, was arrested Tuesday and is currently being held without bail. He is scheduled to appear in court for an arraignment. Details surrounding the investigation, including the specific cause of death and potential motive, have not been publicly released by authorities.

Jill Biden and Stephen Treon were married from 1977 to 1982. She later married President Joe Biden. The First Lady’s office has not yet released a statement regarding the charges against her former husband. The Delaware State Police are continuing their investigation and urging anyone with information to contact them.