MIDLAND (WWJ) – A break in a 25-year-old murder case has led to the arrest of an Oakland County man.

The Attorney General’s office and Midland County Prosecutor announced Friday morning that 51-year old Michael McIntyre, of New Hudson, was formally charged with one count of felony murder and one count of first-degree premeditated murder in the 1991 beating death of his ex-girlfriend’s mother, Diane Ross.

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McIntyre pleaded not guilty to the charges, and a judge set bond at $1 million for each murder charge. McIntyre’s next court appearance will be scheduled at a later date.

Police say Ross, a 43-year-old double amputee with no legs, was sleeping in her Lee Township home when she was viciously beaten by a masked intruder in the early morning hours of August 7, 1991. Ross’ then-5-year-old grandson, who was present at the time, sought help for his grandmother following the beating.

At the time of the murder, Ross’ daughter had recently broken off a relationship with McIntyre. He was interviewed about the murder in 1991, but police didn’t have enough evidence at the time to take him into custody.

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The case went unsolved for 25 years. Detectives reviewed the case in 2012 and additional investigation began in early 2013.

Then in 2014, the Attorney General was asked to join the investigation after a review of cold cases revealed new information in the case. Police say additional witnesses were located and physical evidence was submitted for further review, which eventually resulted in the murder charges against McIntyre.

“This was a great collaboration of agencies that worked in conjunction with each other to take a murder suspect off the street and to make our communities safer,” Midland County Sheriff Scott Stephenson said in a statement.

“Even after 25 years, we believed that it was essential to join together to make sure the perpetrator of this horrific crime was held accountable for his actions,” Midland County Prosecutor J Dee Brooks said in a statement.

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