LOS ANGELES (CBSLA) — Police are investigating after a man was fatally stabbed by an apparent homeless man Wednesday morning at a restaurant in downtown Los Angeles.

According to the Los Angeles Police Department, officers responded at about 8:35 a.m. to a call of a stabbing at Margarita’s Place, a Mexican restaurant in the 100 block of E. Seventh Street.

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The victim, a man in his 50s who lived nearby, was eating when he got into an argument with an apparently homeless patron who then stabbed the victim and fled.

Police said the suspect was carrying the knife when he went into the restaurant.

Security video captured by a nearby business showed the suspect calmly walking away from the restaurant in broad daylight.

According to the owner of the restaurant, the suspect started going to the restaurant a couple weeks ago.

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“He would just order food, and he would sit there quietly,” the owner said. “He wouldn’t talk to anyone. He didn’t show any type of aggression.”

According to the owner, this was the first deadly incident in the 40 years he has owned the restaurant but said there’s been an increase in homelessness in the area as well as aggressive behavior in his restaurant.

“It’s getting wild down here,” Marcus Whittimore, a downtown resident, said.

Whittimore lives near the intersection of 7th and Main, a corner with high-end lofts, and said that in the past few months he’s seen a homeless encampment spring up on his block.

“People are shooting up in the alley right here on Harlem Place all the time,” he said. “I’ve had to jump the fence to call the police to get a guy who was OD’ing and then the ambulance comes by to give him the Narcan or whatever to help resuscitate him.”

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Police said they did not know what prompted the stabbing, but said the men did not appear to know one another.