A man was sentenced to five years in prison Friday and will ultimately be deported after assaulting a student with a hammer in Duques Hall four years ago.

A judge gave Mohammed Niazi the maximum sentence he could have received, calling Niazi’s 2009 attack a “nightmare scenario.” Niazi was convicted in August of hitting a graduate student with a hammer, leaving a 3-inch gash in his head.

“Here is a guy who had never seen Dr. Niazi before,” Judge Stuart Nash said in court Friday about the student. “To this day, four years later, he doesn’t have any idea why someone would ever maul him in the back of the head.”

Charles Murdter, who represented Niazi, said his client would file an appeal.

The 46-year-old Yale University graduate, originally from the United Kingdom, was found guilty of assault with a dangerous weapon, assault with significant bodily injury and carrying a dangerous weapon. The jury acquitted him of assault with intent to kill.

Niazi, who was living in Virginia at the time, entered Duques Hall in December 2009 and attacked the graduate student in a second-floor bathroom. The student suffered major – but not life-threatening – injuries.

“This is a case that I will remember for a long time,” Nash said. “I will go to my grave wondering why this happened. But what I won’t go to my grave wondering is who did it because I know it was you, Dr. Niazi.”

Assistant U.S. Attorney Scott Sroka said the victim did not know Niazi, who claimed he had come to Duques Hall to check if flyers for his tutoring services were tacked on a bulletin board.

After receiving blows to his head, the victim turned around, looked Niazi in the face and tried to ward him off with his arms, Sroka said. Niazi left the bathroom, standing in the foyer between the door and the main hallway, and the victim “barricaded himself in the bathroom until he thought he was safe.”

“As the victim walked out of the bathroom door holding his pants up in one hand and his bleeding head with the other hand, students all over the building rushed to his aid,” Sroka said. “One student took off his own shirt and tried to stop the bleeding coming from the victim’s head.”

Niazi fled to London soon after, but police linked him to the scene with security footage and charges made to his credit card at the Starbucks in Gelman Library. He was apprehended in April 2013 when he attempted to travel through Panama.

Sroka said the victim, a 6-foot-tall man who served in the military, “broke down” when police showed him a photo of Niazi and asked him to confirm whether the man was his attacker.

“He chose not to come to court today mostly because he didn’t want to see that face again,” Sroka said. “And for four years, while the defendant was off in other places around the world, the victim was looking over his shoulder, afraid, apprehensive, wondering what was waiting behind him.”

He added that the “viciousness, the deliberateness of this attack for no apparent reason” pushed the government to ask for the maximum sentence.

A statement from one of Niazi’s former employers explained he was fired months before the assault because of his “rude and hostile tone in the workplace.” Sroka also presented emails that Niazi had allegedly sent to a former associate with “threats of violence, racial slurs and vile obscenities.”

“The threats that the defendant made against his target included a threat to bash that person’s head in,” Sroka said, adding that police had started the process of obtaining an arrest warrant for Niazi but never completed it.

Murdter said Niazi denied ever sending the emails. The same associate also accused Niazi of making bomb threats and called him suicidal and schizophrenic, which Murdter said was an attempt to “incite” the government “particularly when the individual’s name is ‘Mohammed.’”

“Certainly, Mr. Niazi’s life has been turned completely upside down by the arrest, his detention and the trial in this case,” Murdter said, adding that his client was teaching at a university in Ecuador when he was apprehended. “His employability, his reputation, his life has been completely disrupted.”

“I respect the decision of the jury,” Niazi said in court. “But I still maintain their decision is incorrect.”

Niazi was also sentenced to three years of supervised release and given a $300 fine.