Rihanna and SLASH have joined the millions who have turned their prayers to the people of Oklahoma caught up in the state's latest storm tragedy.

Tornados swept through the suburbs of Oklahoma City on Monday (20May13), leaving more than 50 people dead and flattening homes and schools. At least 20 children are among those to have died in the tragedy, many of those students at Plaza Towers Elementary School in Moore, who were killed by falling debris when the storm ripped through the building. At least 145 people are believed to have been hospitalized in the area.

Rihanna and Slash were among those left devastated by the news footage of the powerful storm's aftermath.

Rihanna took to Twitter.com and posted the simple message "Praying for Oklahoma", while rocker Slash added, "Horrible what the people in Oklahoma just went thru. The devastation they're facing now. & the lives they've lost."

Meanwhile, Oklahoma native Carrie Underwood added, "Growing up in tornado alley, you always know what could happen... it doesn't change how devastating it is when something does happen."

And fellow country stars Miranda Lambert and Blake Shelton, who share a home in Tishomingo, Oklahoma, also expressed their concern about the storm tragedy.

Miranda Lambert tweeted, "Pray. That's all we can do. Pray for peace in Oklahoma."

Her husband was in Los Angeles when the tornados hit but had locals in mind as he posted, "Get somewhere safe!!!"

Ellen DeGeneres, Alyssa Milano, Mia Farrow and Marlee Matlin were also among the celebrities who took to Twitter to share their thoughts.