Actress and comedienne Jan Hooks passed away on Oct. 9, Thursday, in New York City, the "Saturday Night Live" alum's reps confirmed to People. She was 57.

Hooks had been combating a serious illness, sources told TMZ.

Details on her death are yet to be released.

Upon the news on her death, several comedians took to Twitter to pay tribute to Hooks.

Describing Hooks as her "comedy gateway drug," comedienne Jamie Denbo tweeted, "Jan Hooks was why I wanted to do comedy. She was my intro to SNL. She was the first person I called the "funniest person!" SO SAD."

"Sam & Cat's" Dan Schneider wrote, "I'm sad and shocked to hear about Jan Hooks passing away. Such a funny, talented performer. I loved her on SNL. Condolences to her family."

"Chelsea Lately's" Fortune Feimster also tweeted, "Noooooo!!! Not Jan Hooks!! I always wanted to be one of the Sweeney Sisters. Ugh, we can't lose any more funny people this year."

From 1986 to 1991, Hooks was a member of the "SNL" cast along with Chris Farley, Dana Carvey, Dennis Miller Mike Myers and Phil Hartman.

On "SNL," she was known as one of the two Sweeney Sisters with Nora Dunn and for her Sinead O'Connor, Kathie Lee Gifford, Ivana Trump and Hillary Clinton impressions.

In 1998, she was nominated for an Emmy for her "3rd Rock From The Sun" performance as Vicki Dubcek.

She was also known for her role as a tour guide at the Alamo in "Pee-wee's Big Adventure" in 1985.

Most recently, Hooks appeared as a guest star on "30 Rock" playing Verna, the mother of Jane Krakowski's character Jenna Maroney.

Before joining "SNL," Hooks dated "SNL" actor Kevin Nealon. After leaving the show, she joined "Designing Women" replacing Jean Smart.

Like many other "SNL" comedians, Hooks got her comedy training at the Los Angeles improvisation and sketch troupe, the Groundlings, according to the New York Times