Celebrities took to Twitter to express their grief after learning the news of Joan Rivers' death on Sept. 4.

She will be greatly missed:

Heaven just got a whole lot funnier. #RIPJoan

Andy Cohen (@Andy) September 4, 2014

Thanks for the laughs @Joan_Rivers ! The last woman to bed me!

Lance Bass (@LanceBass) September 4, 2014

RIP Joan Rivers. A force of nature.

Seth Meyers (@sethmeyers) September 4, 2014

we lost a great one in @Joan_Rivers - she was funny all the way to the end

Jimmy Kimmel (@jimmykimmel) September 4, 2014

Joan Rivers!!! Oh Noooo!!!

Queen Latifah (@IAMQUEENLATIFAH) September 4, 2014

RIP the mighty Joan Rivers. Funny & fearless. Truly one of a kind.

Ricky Gervais (@rickygervais) September 4, 2014

Sending love to @MelRivers and family. What a life and what a woman.

christine teigen (@chrissyteigen) September 4, 2014

A legend, a friend, a mentor, an icon, and wildly funny. One of a kind. RIP #JoanRivers @joan_rivers pic.twitter.com/jnAC5G4AQo

Kathy Griffin (@kathygriffin) September 4, 2014

NOOOOOOOO..........
RIP Joan. You will be forever missed.

Kelly Ripa (@KellyRipa) September 4, 2014

tragic to lose such a funny,warm woman as Joan Rivers. My thoughts, prayers & love go out to her family and friends. You will be missed Joan

Shannen Doherty (@DohertyShannen) September 4, 2014

...My heart goes out to Melissa and Edgar. Love and respect from the Osbourne family to you both.

Sharon Osbourne (@MrsSOsbourne) September 4, 2014

RIP Joan. What a tough trailblazing lady. We've lost so much laughter this year.

josh groban (@joshgroban) September 4, 2014

My heart is broken. Joan Rivers RIP. Gone way too soon. All my thoughts & prayers are with Melissa & her family.

Jesse Tyler Ferguson (@jessetyler) September 4, 2014

My friend Joan Rivers has passed away once again to quote Billy Crystal... There are no words. Bon Voyage Joan

Whoopi Goldberg (@WhoopiGoldberg) September 4, 2014

So funny and irrepressible. Rest in peace, Joan Rivers.

bob saget (@bobsaget) September 4, 2014

pour some out for Joan tn.

lady was a G.

R. Peezy (@RyanPhillippe) September 4, 2014

Love Her or Hate Her, we're gonna Miss JOAN RIVERS! I always
Respected her go for broke humor. One of a kind.R.I.P.

Samuel L. Jackson (@SamuelLJackson) September 4, 2014

Joan Rivers will always be a pioneer. She paved the way for a lot of comedians. Im very sad shes gone. pic.twitter.com/i1uE9fyHMh

Ellen DeGeneres (@TheEllenShow) September 4, 2014

Oh, Joan. Thank you for being so kind to me & making me laugh until tears in those moments I got spend with you. Rest in peace.

Jordin Sparks (@JordinSparks) September 4, 2014

Saddened that Joan Rivers has passed. What a legacy she leaves. Praying for Melissa, Cooper & their family

Candace Cameron Bure (@candacecbure) September 4, 2014

Sad news @Joan_Rivers was one of the hardest working, funniest & sweetest women I've ever met. Twas a pleasure to have known you #JoanRanger

Sarah Hyland (@Sarah_Hyland) September 4, 2014

She gave me my biggest break and inspired me in life. I can't believe that heart stopped http://t.co/aafQYz1uyf

Howie Mandel (@howiemandel) September 4, 2014

A legend. So funny. So kind to me. So sad. Our E! Family, as well as the entire world, is so grateful http://t.co/7RZ0ySetVb

Ross Mathews (@helloross) September 4, 2014

CONDOLENCES 2 @MelRivers AND THE RIVERS FAMILY #RIPJOAN

INSTAGRAM LILJON (@LilJon) September 4, 2014

We will miss you @Joan_Rivers . What you did in your life was absolutely remarkable. Your rep for kindness to everyone was completely true

Joel McHale (@joelmchale) September 4, 2014

RIP Joan Rivers. You made us laugh and happy.

Kristin Chenoweth (@KChenoweth) September 4, 2014

So sad to hear we lost a great person today! #RIPJoanRivers http://t.co/IGCxuqy9BZ

Eva Longoria (@EvaLongoria) September 4, 2014

Joan Rivers has died. What a sad ending to a brilliant and tragi-comic life; one of the bravest, and funniest of all.

Bette Midler (@BetteMidler) September 4, 2014

It was a treat running into Joan in the hallways at E!she was always on... always a riot. Our thoughts are w/ you & your family @MelRivers .

Ryan Seacrest (@RyanSeacrest) September 4, 2014

She was trailblazing. Hysterical. Thoughtful. Well miss you immensely Joan.

Ryan Seacrest (@RyanSeacrest) September 4, 2014

Watching Joan Rivers do standup at age 81 was incredible: athletic, jaw-dropping, terrifying, essential. It never stopped. Neither will she.

Lena Dunham (@lenadunham) September 4, 2014

My heart is torn in half.
She wasn't done.
#Joan http://t.co/XH87wAT4Mb

Sarah Silverman (@SarahKSilverman) September 4, 2014

Very sad to learn about Joan Rivers, a pioneer for women in comedy.

ABFoundation (@ABFalecbaldwin) September 4, 2014

RIP Joan Rivers. Being publicly told that my dress is hideous will never feel quite as awesome. You will be truly missed.

Anna Kendrick (@AnnaKendrick47) September 4, 2014

I loved Joan Rivers. A trailblazing funny lady. Have fun up there. #RIPJoan

Elizabeth Banks (@ElizabethBanks) September 4, 2014

This Woman lived Life to thee fullest!!! You will be missed Always! :( pic.twitter.com/59190aNoz5

ROBERT KARDASHIAN (@robkardashian) September 4, 2014

Incredibly heartbroken...we will miss you so much. Amazing Mother, Amazing Grandmother, Amazing http://t.co/DRUIo7JpL5

Kris Jenner (@KrisJenner) September 4, 2014

I am so sad. May I live my life as full as #JoanRivers did. Today is a sad day, but I will try and laugh to honor her #CanWeTalk #RIPJoan

Sarah Michelle (@RealSMG) September 4, 2014

It was an honor to know you @Joan_Rivers you will always be an entertainment icon R.I.P. pic.twitter.com/AZeMJoozKY

kevin jonas (@kevinjonas) September 4, 2014

I am saddened to learn of the passing of @Joan_Rivers . A comedic legend. Thoughts going out to Melissa and her family.

William Shatner (@WilliamShatner) September 4, 2014

Rest In Peace to the amazing Joan Rivers. very very sad news pic.twitter.com/pU1KcbPnFP

Kendall Jenner (@KendallJenner) September 4, 2014

We'd fuss but love was there. Cant believe ur gone. Love to your family. You were iconic and trailblazing. RIP Joan pic.twitter.com/hV7fH03gfw

Lindsay Lohan (@lindsaylohan) September 4, 2014

Not only was Joan a comic genius, she was an amazing woman. Thank you for always having Kellys back. You will always be a legend. RIP

Ozzy Osbourne (@OzzyOsbourne) September 4, 2014

So sad over the passing of @Joan_Rivers . U brought me a
lifetime of laughter & were amazing to me the few times we met. RIP

Laverne Cox (@Lavernecox) September 4, 2014