Police are investigating a shooting in an Ontario apartment that left two men dead and two others injured Monday night.
Residents at the Vistara Apartments complex said they heard a commotion around 11:30 p.m. on Monday that began with the sound of people shouting at each other.
"I woke up to screaming," said one neighbor, who lives in the complex.
Another neighbor, who did not want to be identified, said that during the screaming he heard around eight muffled bangs, possibly coming from inside an apartment.
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Then the screaming got even louder, sounding like it was coming from a hallway or the parking lot.
Moments later, he heard at least two more bangs and realized they were gunshots.
Police arrived within minutes to the second floor and made a grim discovery: two men dead from gunshot wounds.
One of the men was 19 years old; the other was 21.
"A couple of hours later, we received information of a third male with gunshot wounds at a local hospital. We also contacted a fourth male at this local hospital," said Eliseo Guerrero of the Ontario Police Department.
Investigators say one of the injured men is 22 years old, while the other is 21.
"Whenever I passed them in the hallways, [they're] very friendly residents," said Paul, a neighbor in the complex who did not want his last name used.
He said that two or three young men live in the apartment across from him, where he believes at least part of the shooting took place. He also said he has never had issues with them.
"I guess they could be rambunctious, but I didn't know them to cause trouble or anything like that," he said.
Investigators said it is unclear if there was one shooter or more.