Venus Stewart (PICTURES): Husband Charged with Missing Mother's Murder

ST. JOSEPH COUNTY, Mich. (CBS/WWMT) The case of missing Michigan mother Venus Stewart has turned into a murder investigation.

PICTURES: Venus Stewart Missing

Venus Stewart has been missing since late April. On Wednesday, prosecutors officially charged her estranged husband, Douglas Stewart, with her murder despite having not found her body.

He was arraigned Wednesday and faces one count of open murder, and one count of conspiracy to commit murder.

Venus Stewart disappeared on April 26 from her parents' home in Colon, Mich., south of Kalamazoo. According to Venus' mother, Therese McComb, her daughter had gone outside early that morning in her slippers and pajamas to mail a letter and never came back.

According to CBS affiliate WWMT, investigators explained that they tracked down a man named Richard Spencer, who has admitted to impersonating Douglas Stewart in Virginia as an alibi for the real Stewart.

Douglas Stewart is accused of driving overnight from Virginia, where he lives, to Michigan, luring Venus outside, abducting her, killing her, and then disposing of her body.

Afterwards, he "traveled back to Newport News, where he met with Mr. Spencer," St. Joseph County prosecutor John McDonough told WWMT. "Mr. Spencer gave Stewart back the clothes he had used, then the men went their separate ways."

Venus' brother says Douglas Stewart and Spencer met over the Internet through video gaming. The prosecutor says Spencer was not paid to act as an impersonator and that he has been cooperative in the investigation.

Spencer has not been charged with any crime yet, but he could be in the future.

Now that Douglas Stewart has been charged, investigators say the efforts to find Venus' body will be stepped up once again.

He is due back in court on June 29 for a preliminary exam between prosecutors and his attorney. A preliminary hearing is set for July 1st.