Jurors in Minneapolis convicted a former technology worker at Canadian Pacific of purposely damaging the railway’s computer network shortly after his forced resignation kicked in.

Christopher V. Grupe, 46, of Minneapolis, was found guilty last week in federal court in Minneapolis of intentionally damaging a protected computer, a felony. Grupe now faces likely prison time, but sentencing has yet to be scheduled.

“IT professionals with both substantial technical skills and trusted high-level access to the computer systems on which they work can cause significant and potentially catastrophic damage to businesses and critical infrastructure,” Assistant U.S. Attorney Tim Rank said in a statement. “When they use their skills and access to commit crimes, there should be real consequences.”

Having just returned from a 12-day suspension for insubordination in December 2015, Grupe was told he was going to be fired from his job at the Alberta-based railway’s U.S. headquarters in Minneapolis. However, he was granted the opportunity to resign.

Prosecutors contended that two days after his last day at work, Grupe deleted files and removed or changed passwords on administrators’ accounts, then tried to cover his tracks by wiping his company laptop’s hard drive before returning it.

Canadian Pacific discovered the damage a few weeks later and hired an outside security company to determine who was responsible.

One of Grupe’s attorneys said Wednesday that he sought a deal to allow his client to admit to a misdemeanor, but the prosecution wouldn’t budge off the felony count, pointing out that Grupe’s misdeeds caused roughly $30,000 in damage.

Now, attorney Daniel Mohs said, “My focus is on the sentencing and trying to keep him out of prison. But that is going to be difficult, but not impossible.”

Mohs said Grupe, who spent 28 years in the military and served in Iraq, had a spotless personnel record in his two-plus years with Canadian Pacific until “he had a confrontation with his immediate boss, yelling at him and using some language he probably shouldn’t have.”

The attorney attributed the outburst and Grupe’s retaliatory crime to stress caused by “working around the clock.”

“I think he was just overworked,” said Mohs, adding that Canadian Pacific has a “company culture” of making salaried employees such as Grupe work 60 to 70 hours a week.

A Canadian Pacific spokesman said Wednesday that the company is not commenting about the case or the allegation that salaried employees are forced to put in well beyond 40 hours a week.