investigators are now examining social media posts that they believe could be by the alleged shooter including a potential warning the gunman possibly discussing online about his plan to kill others. mercy medical center the major hospital in the roseburg area tells cnn they have received nine patients. they're expecting three more. they asked the public to, quote, please continue to pray. let's get right to cnn justice correspondent pamela brown. give us the situation on the ground right now. the tick tock of how this trage tragedy. >> this situation unfolded after classes started around 10:30 this morning at umpqua community college. we learned a man in his 20s walked into one of the school buildings there on campus and opened fire in multiple classrooms. and as we've learned he killed at least ten people according to preliminary reports. we know federal authorities are responding. the atf bringing in their canine units. and the fbi also responding in what is a very active