"When you have such a large campus community, you're going to have a bad apple here and there," Detective Lieutenant Ray Cote said.
Police say five Hofstra University students concocted a scheme that backfired. At the center of it all, police said, was Gregory Sable.
"I just knew he was an RA, saw him in the office a few times never talked to him," Hofstra student Jack Swanson said.
The 22-year-old told police he had he had been robbed around 8:00 Thursday night inside his room at New Complex, a freshman dorm.
What he left out -- he allegedly had been selling drugs out of the same room for several months.
Upset over the quality of a previous purchased of cocaine from Sable, another student, Michael Smith, came up with a plan to teach him a lesson, investigators said.
Yet another student, Adi Stern, got involved, according to police. He came to Sable's room to purchase cocaine from Sable, and then wearing ski masks and carrying what appeared to be real guns, Timothy Gallo and Smith stormed the room.
"They taped Mr. Sable up and pistol whipped him and forced his suite mate into confinement," Cote said.
Christian Webster was waiting outside in a car.
Police ended up finding more than $5000 in cash, what turned out to be pellet guns and loads of real guns.
"Public safety was outside. I couldn't get inside, went upstairs and was on lock down for an hour," Katie Friedman said.
But some students, now knowing what happened, were upset school officials didn't do more.
Hofstra University issued a statement: "We had used the campus alert notification the night before when there was an incident off campus, but last night because the incident was targeted and happened fast and was wrapped up. The system was not used"
Gregory Sable faces drug charges. Adi Kauf-Stern and Christian Webster were charged with robbery, weapons and drug offenses.
NEW YORK AND TRI-STATE AREA NEWS