(NewsNation) — Students at Michigan State University spent hours sheltering in place after a shooting on campus Monday night.

For four hours, students on MSU’s campus waited for police to give the all-clear, not knowing whether their friends were among the victims.

“We got an email sent out just to lock down and stay in your dorms. Nothing over the loud speakers just kind of sitting here waiting,” MSU student Joey Pricko said.

After getting an MSU alert instructing them to “run, hide, fight” some students spent their time listening to police scanners for second by second updates. Three students told NewsNation’s Ashleigh Banfield those led them to wrongly believe there were multiple shooters.

“We mean multiple shooters. We believe there’s more than one, maybe two. Couple more. We’re not sure. Everyone we’ve been talking to and we’ve been listening to a police broadcast station, so we believe there’s more than one,” Pricko said.

That’s one of the pitfalls of monitoring police transmissions in an ongoing and unclear emergency situation. In East Lansing, it could also have been dangerous, had the shooter been listening as the police spoke openly about where they planned to take witnesses.

Media organizations and community advocates often rely on the technology in times of crisis. Scanners can easily be obtained online or in app stores.

But some police agencies across the country have moved to keep the information private or encrypt the radio channels they use, arguing that scanners compromise the privacy of victims or witness and can place officers at risk.

This year, Chicago plans on encrypting all of it’s real-time police radio communications, in a move opposed by news outlets who vet and then rely on that information for reporting purposes.

Other cities, like San Francisco, Denver and Louisville have encrypted their police frequencies. Las Vegas does the same for the general public, but exempts credentialed media organizations.