Update, 4 p.m. Eastern: Two people injured in today’s shooting have now passed away of their injuries.

A suspect was in custody and being treated at a local hospital after a Thursday morning shooting that injured several people at Saugus High School, including two males and a female who were reportedly in critical condition, officials said.

“Suspect is in custody and being treated at a local hospital,” Los Angeles County Sheriff Alex Villanueva tweeted.

Two male patients and one female patient were in critical condition at Henry Mayo Hospital, with another male patient in good condition, the medical center tweeted.

It wasn’t immediately clear if there were other injuries, either as the result of the gunfire or sustained in the aftermath — as the number of total injuries fluctuated between three and seven in numerous reports throughout the morning.

Authorities had also said one person required CPR at the scene.

Investigators locked down all schools in the William S. Hart Union High School District for about an hour as they searched for the suspected gunman, but school officials said around 12:10 p.m. ET that all lockdowns, except at Arroyo Seco and Saugus, were lifted.

The Santa Clarita Sheriff’s Department said they “believe at this time that there is only one suspect but we are actively investigating and following all leads.”

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It was not immediately clear if the shooting occurred inside the school building, on school grounds or near the school.

It also wasn’t clear what time the shooting happened, but a lieutenant with the fire department told Fox News school began at 6:55 a.m.

“Deputies on scene and still responding,” the department tweeted.

“Avoid the area. Further information to follow.”

President Donald Trump “is monitoring the ongoing reports of a school shooting in Santa Clarita, CA,” the White House said in a statement.

“The White House encourages all those in the area to follow the advice of local law enforcement and first responders.”

Saugus High School is located 40 miles northwest of Los Angeles.

Several students were transported out of the school on gurneys, and at least one person was discovered wounded inside of the school’s choir room, the Los Angeles Times reported.

This is a developing story; please check back for updates. Nicole Darrah covers breaking and trending news for FoxNews.com. This Fox News piece is used by permission.

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