An Elmwood Park man ambushed a fellow chef in the kitchen of a Portage Park restaurant during the dinner rush Sunday, fatally stabbing him with a 9-inch fillet knife for several minutes as he fended off coworkers trying to stop him with cutting boards and a chair, prosecutors say.

Jesus Martinez, 37, was charged Wednesday with first-degree murder in the murder of 35-year-old Cory Neill, who both worked as chefs at the Foundation Tavern and Grille, 5007 W. Irving Park Rd., according to Cook County prosecutors.

Martinez, whose only prior offense is a misdemeanor DUI in 2007, may have been motived by the false belief that his coworker broke into his home and attacked his family, prosecutors allege.

Martinez was denied bail Wednesday during a court hearing in which Assistant State’s Attorney James Murphy said there is “crystal clear” video surveillance in the kitchen showing the encounter, according to a proffer outlining the case.

The video first shows Neill and Martinez working side-by-side at the grill and oven area over a period of time, with no unusual behavior or arguments between the two, he said.

When other employees walked out of the room, leaving the pair alone in the kitchen at 6:53 p.m., Martinez left for the basement after appearing to tell Neill to watch what he was cooking on the stove, Murphy said.

Martinez walks off camera and returns 20 seconds later holding the knife, and walks briskly toward Neill, grabbing him from behind and stabbing him repeatedly, Murphy said.

The video shows Neill fall to the floor as Martinez stood over him while continuing to stab him, Murphy said.

Several coworkers rushed back into the kitchen and tried to disarm Martinez, but he fought them off, Murphy said.

“The employees tried to use cutting boards and a chair to disarm and subdue the defendant, but none of it worked,” Murphy said in the proffer. Martinez remained on top of Neill, and pointed the knife at anyone who approached, Murphy said.

After four minutes, a Chicago police officer entered the kitchen, gun drawn, and ordered Martinez to drop the knife, Murphy said.

Martinez complied and was arrested. He then told investigators that Neill broke into his house and sexually assaulted his daughter and cut his son, Murphy said. Prosecutors said the allegations were not accurate, and were refuted by Martinez’s wife.

Martinez worked in the restaurant for about a month before the stabbing and was described by staff as a quiet worker, Murphy said.

Neill, of suburban Stickney, was rushed to Illinois Masonic Medical Center and died during surgery, Murphy and the Cook County medical examiner’s office said.

The owners of Foundation Tavern and Grille said in a Facebook post they were “devastated” to announce the death of Neill.

“He was always cooking with a smile and brightening the days of all of those who had the pleasure of spending time with him,” the restaurant owners said in the post.

“He was truly passionate about his craft and was always looking for ways to improve the kitchen and the establishment as a whole. Our family will not be the same without Cory.”

The owners said they closed the restaurant on Tuesday in his remembrance.

Neill’s half-brother Dylan Koempel said he was still coming to grips with the news of his sibling’s murder.

“Obviously, the man didn’t deserve it. He was taken just because someone was a little bit irritated at work, and that’s unfair,” Koempel said.

“This man was the greatest person to so many people and I hope everybody involved knows that he loves them so much.” He said Neill was born in Aurora and has a 4-year-old son.

Joe Wolfe, who said he grew up with Neill in Berwyn, said his friend “was an all-around great soul” who had a passion for music and food.

Another friend, Justin Thorndyke, said he remembers Neill as an “amazing person” and a “sweet guy” from when Neill performed under the name “DJ Hindsight.”

“He spun jungle and dubstep,” Thorndyke said. “He was passionate about reaching people’s hearts through music.”

Ald. James Gardiner (45th) said in a statement he was saddened to hear of the loss of life.

“My thoughts and prayers are with the family of the victim during this difficult time,” he said.

An online fundraiser raised more than $4,000 by Wednesday afternoon to pay for funeral expenses. Visitation will be held 4 p.m. Friday at the Dieterle Memorial Home at 1120 S. Broadway Ave. in Montgomery.

Martinez is due in court again Dec. 30.

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