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(CNN) – When Sgt. Bowe Bergdahl first joined his squad in Afghanistan, he was a "good soldier," says former U.S. Army Staff Sgt. Justin Gerleve, Bergdahl's former squad leader.
"He listened to what we needed to do, and got done what he was asked to do. He was willing to train, and always asked a lot of questions on what needed to happen," says Gerleve.
But the former Army staff sergeant says he believes Bergdahl "totally deserted not only his fellow soldiers, but also his leadership."
According to firsthand accounts from soldiers in his platoon, Bergdahl shed his weapons and walked off the observation post with nothing more than a compass, a knife, water, a digital camera and a diary.
"He didn't want anything to do with us anymore," says Gerleve.
Like many other soldiers, Gerleve says Bergdahl is not a hero, and did not – as NSA director Susan Rice said Sunday – serve with honor and distinction. The soldiers who searched for him, he says, are the true heroes.
Many soldiers in Bergdahl's platoon said attacks seemed to increase against U.S. soldiers in Paktika province in the days and weeks following his disappearance.
"The attacks did get more direct, the IEDs did get more pinpoint to our trucks," said Gerleve. "I can't say for sure the leakage came from Bergdahl, but it's kind of that suspicion that it did happen."
Within days of Bergdahl's disappearance, former Army Sgt. Evan Buetow told CNN, teams monitoring radio chatter and cell phone communications intercepted an alarming message: The American is in Yahya Khel (a village two miles away). He's looking for someone who speaks English so he can talk to the Taliban.
Gerleve also heard the intercept, and says there is no doubt the message referred to Bergdahl.
"There was no other American out there, running around ... except for him on that day," says Gerleve.
At least six soldiers were killed in subsequent searches for Bergdahl, according to soldiers involved in the operations to find him. The Pentagon was not able to provide details on specific operations in which any soldiers killed during that time were involved.
Echoing reactions of other soldiers in the platoon, Gerleve says he blames Bergdahl for the deaths.
"If he wouldn't have deserted us, these soldiers very well could have been in a different place at a different time," says Gerleve.
But rescuing Bergdahl was the right call, he says.
"No American needs to be left behind. But ... he needs to be accountable for his actions, accountable for what he did, and he needs to withstand a trial," said Gerleve.
The Army will review the case Bergdahl "in a comprehensive, coordinated effort," Secretary of the Army John McHugh said Tuesday.
The review will include speaking with Bergdahl "to better learn from him the circumstances of his disappearance and captivity," he said.