WASHINGTON - NBA superstar LeBron James and several Major League Baseball stars were among those who expressed their shock and sorrow over a mass shooting Friday by a gunman at a US elementary school.

At least 27 people, including 18 children, were reportedly killed at Sandy Hook Elementary School in Newtown, Connecticut.

"WTH!! Once again our country is going through another horrific tragedy. Prayers goes out to all the families in Connecticut. I'm sick!" tweeted James, the NBA's Most Valuable Player who led the Miami Heat to last season's NBA title.

WTH!! Once again our country is going through another horrific tragedy. Prayers goes out to all the families in Connecticut. I'm sick!

— LeBron James (@KingJames) December 14, 2012

"Like what makes someone wanna do that. C'mon now! DAMN IT. Innocent victims just gone."

Like what makes someone wanna do that. C'mon now! DAMN IT. Innocent victims just gone

— LeBron James (@KingJames) December 14, 2012

Evan Longoria, a slugger for the Tampa Bay Rays, tweeted: "My deepest and sincerest thoughts and prayers go out to all families affected by the CT tragedy today. It makes me sad."

My deepest and sincerest thoughts and prayers go out to all families affected by the CT tragedy today. It makes me sad.

— Evan Longoria (@Evan3Longoria) December 14, 2012

The tragedy came a day after Shane Victorino signed a new free agent contract with the Boston Red Sox.

"So sad get done training and turn on news to this tragic shooting in Connecticut. My thoughts and prayers go out to all involved," Victorino tweeted.

So sad get done training and turn on news to this tragic shooting in Connecticut. My thoughts and prayers go out to all involved

— Shane Victorino (@ShaneVictorino) December 14, 2012

"Embrace your children, give them a hug/kiss and be thankful for the many blessings! It's hurting my heart to see this senseless act."

Embrace your children, give them a hug/kiss and be thankful for the many blessings! It's hurting my heart to see this senseless act

— Shane Victorino (@ShaneVictorino) December 14, 2012

Justin Verlander, the Detroit Tigers pitcher who helped his team reach the World Series last October, tweeted: "This is beyond a tragedy and should never have happened. Thoughts and prayers are with everyone affected."

This is beyond a tragedy and should never have happened. Thoughts and prayers are with everyone affected.

— Justin Verlander (@JustinVerlander) December 14, 2012

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