SIKESTON, Mo. -- An autopsy has ruled out a Friday knife injury as the cause of a man's death Monday.

An autopsy Tuesday at Mineral Area Hospital in Farmington, Missouri, found Tony Allen Burns, 30, who had been stabbed in the neck allegedly by his girlfriend the previous week, probably did not die because of the wound.

"The exact cause of death is yet to be determined, as this is a preliminary report from the coroner's office," said Capt. Jim McMillen, Sikeston Department of Public Safety public information officer, in a news release. "It will be several weeks before the results of the microscopic and toxicology results are able to be released."

On Monday, Sikeston officers were called to 236 William St., where they found Burns dead in bed. At that time, officers began an investigation, and coroner Scott Amick was contacted.

On Friday, "Burns was transported to an area hospital and underwent treatment for the knife wound to his neck but had since been released from the hospital," McMillen said. "Burns was apparently resting at home when he died."

The girlfriend, who was arrested after the stabbing incident Friday, was later released when it was determined the case lacked sufficient probable cause for charges, he said.

"All death scenes (accidental or otherwise) are investigated completely in case we later discover that a homicide occurred," McMillen said. "Sometimes this is obvious, and other times not so much. We should know more about the cause of death after all the autopsy results are obtained. However, sometimes toxicology results take weeks to acquire."