Former Saturday Night Live star Jan Hooks passed away earlier today in New York City, at the age of 57. While no cause of death was given, TMZ sources say the actress was suffering from a serious illness.

After coming up through the Los Angeles-based comedy troupe The Groundlings, Jan Hooks appeared in the TV series Not Necessarily the News and had film roles in Pee-Wee's Big Adventure and Wildcats, before joining the cast of Saturday Night Live in 1986.

The actress starred alongside some of SNL's biggest and brightest stars, such as Chris Farley, Mike Myers, Dana Carvey, Phil Hartman, Kevin Nealon and Dennis Miller as a part of the main cast between 1986 and 1991.

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She also came back for a number of appearances in 1993 and 1994, where she played First Lady Hillary Rodham Clinton alongside Phil Hartman as President Bill Clinton. She was best known for the Sweeney Sisters sketch alongside Nora Dunn, and for her impressions of singer Sinéad O'Connor and actress Bette Davis.

After her stint on SNL, the actress appeared in Designing Women, 3rd Rock from the Sun, and voiced Manjula Nahasapeemapetilon on The Simpsons. Her last acting credit was guest-starring as the mother of Jane Krakowski's Jenna Maroney on NBC's 30 Rock.