By CBSLA Staff

WILLOW BROOK (CBSLA) –  Three of the four people injured Friday in a shooting at the Willowbrook/Rosa Parks Metro station remain hospitalized, listed in critical condition with stable vital signs.

The effort to identify the three shooting suspects continues.

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A fourth victim had less severe wounds, according to Ramon Montenegro, a public information officer with the Los Angeles County Sheriff Department’s Transit Services Bureau.

Montenegro also one of the suspects brandished a firearm at a fifth victim, though that person was not injured.

A witness to Friday night’s shooting, which was reported at about 7:40 p.m., said the incident started with an argument.

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“At first it was an argument right where the two trains…the two cars connect together,” said Andrew Maynard, “and I was part-way through the second one. And then I just saw a young Hispanic man pull out a gun and start shooting. He shot three times and then more arguing and pushing and shoving. Then they shot two or three more times. As the one man ran towards me to get away from them, they shot him in the leg and then he collapsed right next to me. But by that time, I was already crouched down and trying to hide behind a little piece of thin metal.

Detectives were looking at security video to see what led up to the shooting and where it occurred. At this time, they do not know if it happened onboard the train or at the station.

Authorities were searching for three possible suspects, though the sheriff’s department could not provide a suspect description.

Service on the Green Line was interrupted overnight for the investigation, with bus shuttles providing bridge service. Full service was restored at about 8:30 a.m. Saturday, Metro tweeted.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)