SAGE TWP. (WWJ/AP) – Authorities say a robber attacked and critically injured a mid-Michigan gun store owner.

Investigators responded to Guns and Stuff in Gladwin County’s Sage Township Monday afternoon after a robbery was reported. When police arrived, they found the shop’s owner, Richard Robinette, lying on the floor with severe head injuries.

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Robinette, whose home and business are located on the same property, was rushed to the hospital, where he was last listed in critical but stable condition. Family members say Robinette is being kept under a medically induced coma.

The suspect, described as a masked man, remains at large.

Police say Robinette sustained head injuries, but have not elaborated on what caused them. Authorities have said the attacker took an unknown number of firearms from the shop, located about 90 miles north of Lansing.

The Federal Bureau of Alcohol, Firearms, Tobacco and Explosives is offering a reward up to $5,000 for recovery of any weapons stolen from the store, as well as for leads on the culprit. That reward amount could be matched by the National Shooting Sports Foundation, bringing the total potential reward to $10,000.

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“This crime is especially heinous since the owner of the gun store was savagely attacked and is in critical condition,” Gladwin County Sheriff Michael Shea said in a statement.

“The Galdwin County Sheriff’s Department is asking that anyone with information that would lead to identifying those responsible to come forward. This is a crime we take very seriously and will pursue those responsible,” he continued.

Charles Rowan and Rosalinda Martinez are wanted for questioning by police in Gladwin County.

Charles Rowan and Rosalinda Martinez are wanted for questioning by police in Gladwin County.

Shea said investigators are looking to speak with Charles Rowan, who has been identified as a person of interest in the case. Police say they’re also looking for Rosalinda Martinez, who apparently called 911 from the gun store as it was being robbed. Martinez spoke to officers at the scene, but hasn’t been heard from since then.

Anyone with information is asked to contact the sheriff’s department at 989-426-9284 or the ATF Flint Field Office at 810-341-5710.

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