Vanessa Marquez, who gained attention last year when she said George Clooney helped blacklist her from Hollywood, died at a hospital following Thursday's shooting at her apartment in South Pasadena, just outside Los Angeles.

South Pasadena police officers responded to a call from Marquez's landlord that she needed medical help. When they arrived she was having a seizure, Lt. Joe Mendoza with the Los Angeles County Sheriff's Department said Friday.

Paramedics treated Marquez, 49, who improved and began talking with three officers and a mental health clinician who spent an hour-and-a-half trying to talk her into getting medical help, Mendoza said.

Marquez became uncooperative, appeared unable to care for herself and seemed to have mental health issues, he said.

At some point, Mendoza said Marquez got what turned out to be a BB gun and pointed it at the officers, prompting two of them to shoot.

"It looked like a real gun," he said, adding that it's unclear where the gun was during her lengthy interaction with police.

The officers were wearing body cameras but footage won't be released for at least six months pending the investigation, Mendoza said.

Terence Towles Canote, a close friend of Marquez's, said the actress was having health and financial problems but that she showed no signs of depression or other mental troubles. She still talked about her dream of winning an Oscar one day and was hopeful for a career comeback, he said.

"She was looking forward to life," Canote said. "This is not a woman who wanted to die."

Marquez posted extensively on Facebook and elsewhere about her health problems, saying she was terminally ill and had seizures and celiac disease, an autoimmune disorder that can damage the small intestine if gluten is ingested.

In 2014, she said in an online post that she had spent her life savings on doctors and hospitals who didn't properly treat her and that she couldn't work or "do most basic everyday functions."

Marquez had a recurring role during the first several years of "ER," which ran from 1994 to 2009. She also appeared on episodes of "Seinfeld," ''Melrose Place" and "Malcolm & Eddie" but her career largely fizzled after "ER."

Marquez gained attention last year after tweeting that Clooney helped blacklist her from Hollywood when she complained about sexual harassment and racist comments among their "ER" co-stars. Clooney said in a statement to "US Weekly" at the time that he was just an actor on the show and was unaware of any effort to blacklist her.

"If she was told I was involved in any decision about her career then she was lied to," he said. "The fact that I couldn't affect her career is only surpassed by the fact that I wouldn't."

In one of her social media posts, Marquez talked about being grateful to be a part of "Stand and Deliver," a 1988 film about a math teacher who motivated struggling students at a tough East Los Angeles high school.

"If you're truly fortunate, you get to live your dream and do the work you were put on this Earth to do," she wrote. "If you're really, really fortunate you do a film that makes history and affects the lives of millions of people ... It will live on long after we're gone."