Former ER actress Vanessa Marquez has been shot dead by police in the US.

The incident happened in the city of South Pasadena, just outside Los Angeles.

Police were called to an apartment to carry out a welfare check on a woman possibly suffering from a medical condition and mental health issues.

When they arrived at the scene, they noticed the woman was having seizures and called paramedics to the scene.

However, police say she became uncooperative "and appeared to be unable to care for herself".

After officers spoke to her for more than 90 minutes, the woman is said to have armed herself with a BB gun resembling a handgun and "pointed it at the officers".

She was then shot dead by police.

Los Angeles Sheriff's Department, which is assisting in the investigation, confirmed the woman was 49-year-old Vanessa Marquez.

The actress was best known for playing Nurse Wendy Goldman in the hit medical show ER between 1994 and 1997.

She also had small roles in a number of other films and TV shows, including Seinfeld and Stand and Deliver.

US media reported that Ms Marquez had been suffering from a number of health issues.

According to the Hollywood Reporter, Ms Marquez last year accused ER star George Clooney of helping to get her blacklisted following complaints she made about alleged misconduct male co-stars on the show.

Mr Clooney said he had "no idea" the actress was blacklisted, adding: "The fact that I couldn’t affect her career is only surpassed by the fact that I wouldn’t".