BALTIMORE (WJZ) — Authorities reportedly found multiple guns – including an AR-15 style rifle – and a list of grievances against fellow students at the home of a Montgomery County honor roll student charged with bringing a loaded gun to school last week.

The incident at Clarksburg High happened just one day after the school massacre in Parkland, Florida.

During a search of 18-year-old Alwin Chen’s Germantown home, authorities report finding several guns, ammunition, replica grenades, a detonator for C4 land mines, a ballistic vest, and a list of grievances against his fellow students.

Officials say a student tipped off school authorities and Chen was arrested for bringing a loaded gun and knife to school.

More information from police on guns recovered in Clarksburg High School student’s home @cbsbaltimore pic.twitter.com/mxrkRU7VMz — Mike Hellgren (@HellgrenWJZ) February 20, 2018

Prosecutors and a Montgomery County police officer spoke in court Tuesday regarding the charges against Chen, and they allege he had brought a gun to school once before.

“I am very thankful that school students have a good enough relationship with the security officers in our schools, someone went to someone and alerted them. That’s a very good thing,” said Montgomery County State’s Attorney John McCarthy.

Some students found out about the incident via social media.

“They weren’t really scared. They were just more shocked and thankful that nothing happened,” one student said.

The school’s principal said “Weapons of any type are not permitted on or near school property. Any student caught with a weapon will be referred to law enforcement and punished accordingly.”

“I think that at this point in stage and time in society that we need to get some metal detectors in here because unfortunately it’s going to happen,” the mom of a student said.

Chen’s parents didn’t speak publicly Tuesday, but his attorney did.

“People here in Maryland are allowed to have weapons and the fact that weapons exist in a home doesn’t make somebody guilty of anything. It doesn’t make somebody a danger,” said David Felsen, Chen’s defense attorney.

Chen was charged with possession of a handgun, possession of a firearm by a person under 21 years old and possession of a firearm on school property after the incident.

Police say no specific threats were made in his journal and they don’t believe the weapons were stolen.

Chen is in jail with no bond.

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