A gunman, aged 20, opened fire at Sandy Hook Elementary School in Newtown on Friday morning, and reports suggest 26 people - 18 of them children - were killed, including the shooter.
First responders and police officers are still at the scene trying to contain the area and reunite parents with their kids, and now a number of celebrities have taken to Twitter.com to express their horror as the tragedy plays out on live TV.
A post written by mum-of-two Alba reads: "One child is confirmed dead in Newtown shooting - this is just awful. My heart goes out 2 all affected... So sad", while Carell continued, "Pray for Sandy Hook, Newtown CT."
Shocked Moore added, "Absolutely devastating news this morning. There are no words.Thoughts, prayers and love to all in Newtown," and Oscar winner Spacey stated, "Just heard about the shooting in Connecticut. My thoughts go out to all who are dealing with this sad news."
New mother Hilary Duff tweeted, "Oh my. I am shocked. Heartbroken. Devastating news about this elementary school shooting. What is wrong w/ people? Praying hard 4 these family's (sic)," and actor David Boreanaz wrote, "Beyond shocked and sad... Pray."
Meanwhile, supermodel Christy Turlington hopes lawmakers will take note and push for tighter gun laws, asking, "How many of these horrible shootings can our society tolerate before we change these gun laws?" and Glee star Jenna Ushkowitz echoed the same sentiment: "My heart goes out to all the Families and children affected by the CT shooting. When will the violence end?"
Other celebrities who took to social networking sites to add their prayers for the victims of the latest school shooting spree include actresses Christina Applegate, Jennifer Love Hewitt, Courteney Cox, and Holly Robinson Peete, as well as singer JoJo and musician Moby.