"I think it was first, you know, just shock. We see it all time, but when it's something that impacts you directly, it hits a little different," David Astrein, a Michigan State University alumnus, said.
Astrein was born and raised just outside of Detroit, Michigan, but has lived in Houston for over 10 years, working as an HR director for a local company.
He went to Michigan State for both undergrad and grad school, graduating in 2008.
"I go back, and I recruit for people to come to Houston for the company that I work for now, where we've taken recruitment trips, and we have students there," Astrein said.
During those terrifying moments of uncertainty, he said the student he knows was texting him back, letting him know that he was in hiding.
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"It's a helpless feeling. It's shock. It's anger. It's all of that," Astrein said.
Authorities said the shooter ended up shooting himself and had no connection to the university.
In a statement, MSU wrote: "We cannot begin to fathom the immeasurable amount of pain that the campus community is feeling."
According to a report by Gun Violence Archive, so far this year, there have been a total of 67 mass shootings, and many, like Astrein, are wondering when this will stop.
"Let's get down to the root of it and figure out how we can prevent this from happening," he said.
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