SAN DIEGO (CBS 8) - News of Thursday's mass shooting at an Oregon college spread quickly across social media. From students at the campus to presidential candidates and celebrities, the shooting has people reacting.

 A gunman opened fire at a rural Oregon community college Thursday, killing at least nine people before dying in a shootout with police, authorities said. One survivor said he demanded his victims state their religion before he started shooting.

The killer was identified as 26-year-old Chris Harper Mercer, according to a government official who was not authorized to speak publicly and provided the name on condition of anonymity. Authorities shed no light on his motive and said they were investigating.

[Related Story: Oregon State Police: Multiple fatalities in community college shooting

The shooting happened at Umpqua Community College in Roseburg, about 180 miles south of Portland. 

One survivor said he demanded his victims state their religion before he started shooting.

Many students, teachers and prominent names took to Twitter to express their condolences, thoughts, prayers, outrage and need for better gun control in wake of this latest mass shooting.

https://twitter.com/PatDooris/status/649782083720642561

https://twitter.com/WhiteHouse/status/649711478925324288

https://twitter.com/mxnders_/status/649683720077635584

https://twitter.com/GabbyGiffords/status/649675223306907648

https://twitter.com/elle_rappe/status/649657590880710657

https://twitter.com/jblackwooducc/status/649645682454740992

https://twitter.com/JebBush/status/649657999355678720

https://twitter.com/HillaryClinton/status/649706544704167936

https://twitter.com/SenSanders/status/649671367239987200

https://twitter.com/jimmykimmel/status/649719208683573248