Investigators are scouring a heavily wooded area in Tennessee to find an armed special forces veteran suspected of trying to kill his wife, officials said.

Craig Berry has been on the run since early Friday after he shot his wife in Dover, on the northwestern fringe of Tennessee near the Kentucky border, according to the Stewart County Sheriff’s Office, the lead investigative agency in the case.

“The suspect fled into the woods near the residence before deputies arrived,” the sheriff’s office said.

The sheriff’s office said it is working with the US Marshals Service. The Tennessee Bureau of Investigation is also assisting with the search, a spokesperson told CNN.

A warrant has been issued accusing Berry of second-degree attempted murder, the sheriff’s office said. His wife has since been released from the hospital, the sheriff told CNN on Tuesday.

The arduous manhunt is especially challenging given the suspect’s skills outdoors. “Berry is a retired special forces veteran and has extensive training in survival tactics,” the sheriff’s office posted Monday on Facebook.

“He is an excellent swimmer and diver, and is in good physical shape. He is armed with at least one handgun and is believed to have taken extra ammunition.”

Search crews are also hindered by the rough terrain. About 30 miles from Dover is the Land Between the Lakes National Recreation Area, considered “one of the largest contiguous blocks of undeveloped forest in the eastern United States.”

A trail camera captured an image believed to be of Berry wearing camouflage clothing, investigators said.

“We are not ruling out the possibility that he has received some outside assistance after the incident,” the sheriff’s office said. “We have no information that he is no longer in the area.”

Stewart County Middle School was on a “soft lockdown” early Monday, meaning all students and staff stayed indoors while instruction continued and “no outdoor activities were permitted while the situation was being assessed,” Stewart County Schools posted on Facebook.

There was “no direct threat to any school whatsoever,” the district’s director of schools, Mike Craig, told CNN on Tuesday. He said law enforcement activity took place at least five blocks away from the middle school.

“We did not let any parents know in advance because we did not want to impact their operation and there was not a direct threat on the school,” Craig said.

The manhunt evoked memories of another search for a suspect that haunted Stewart County for days.

In 2018, murder suspect Kirby Wallace evaded authorities for a week, CNN affiliate WTVC reported. He was eventually captured and later pleaded gulity to murder, attempted murder, burglary, robbery, kidnapping and arson.

This is a developing story and will be updated.

CNN’s Sharif Paget contributed to this report.

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