In the week after Nikolas Cruz, 19, was charged with killing 17 students and faculty Feb. 14 at Marjory Stoneman Douglas High School in Parkland, Fla., many Northeast Ohio school districts have responded to threats of pending gun violence, some found to be credible and several dismissed as online rumors. This list of threat activity is not comprehensive, rather what is known from news, police and school reports.

February 15

• A verbal threat made before the Florida school shooting against Copley High School becomes known to police and school officials. The student has been disciplined, Superintendent Brian Poe said.

February 18

• A 14-year-old student in Bedford posted an image of a handgun on Instagram and threatened to shoot students from Green Middle School — the student’s old school — during an online argument. He was charged with telecommunications harassment, a first-degree misdemeanor, and taken to the Summit County Juvenile Detention Center.

• Police arrest former Manchester High School student Caleb Pribonic, 18, after a video is shared on Snapchat. Authorities say Pribonic is the masked man waving a gun and threatening to send eight bullets toward his former high school, and an administrator there.

February 19

• Authorities trace a midnight Snapchat post — “I hate people, Florida pt. 2?” — to a 16-year-old Ellet High School student. Police say the student indicated plans “to shoot up” the school and admitted to the threats.

• A Facebook post is forwarded to police that a student will attack Firestone High School at 2 p.m. with a rifle, a handgun, nerve gas and a pressure cooker explosive. The empty threat had been recycled on social media from a year earlier.

February 20

• Keith Simons, 13, conceals a .22 rifle, extra ammunition and bottle rockets on his morning bus ride to Jackson Memorial Middle School. He is found in the boys’ rest room with an apparent self-inflicted gunshot wound. He dies the next day. Whether his death was an accident or intentional is unknown.

• Tallmadge police find no credible evidence that a shooting took place at Tallmadge High School, as rumored. Still, police maintain a presence at all schools.

• Alliance police swarm the high school but find no evidence that a shooting will take place that day after Facebook users circulate rumors. The threats turn out to be credible the next day.

February 21

• Five Alliance High School freshmen are arrested after school resource officers overhear them planning a shooting at a lunch table. Police find evidence of weeks of planning. The students say it’s a joke. They’re all sent to Faircrest Juvenile Attention Center on misdemeanor charges of false alarm.

• Canton police arrest a 16-year-old McKinley High School student who, again on Snapchat, allegedly threatened violence the next day at McKinley and GlenOak high schools. She’s charged with inducing panic, making terroristic threats and telecommunication harassment.

• Streetsboro police investigate a possible threat on social media. Mayor Glenn Broska had proposed the day before that the school raise $500,000 to hire armed sentinels.

• Waterloo Local Schools use Facebook to pre-empt potential rumors or threats, saying the Portage County Sheriff’s Office has provided extra presence in the district. Marlboro police make it known they are staffing schools there.

• Coventry Local School District officials notify police about Erin Croghan, a parent, who allegedly is spreading a false rumor on Facebook of a gun in a middle school locker. She’s charged with inducing panic, a first-degree misdemeanor.

February 22

• Perry Township police arrest a 13-year-old student for allegedly threatening to shoot up Edison Junior High School the day before. The student was charged with inducing panic, a second-degree felony, and aggravated menacing, a first-degree misdemeanor.

• A 17-year-old Cuyahoga Falls High School student is arrested and faces charges of inducing panic after police say the student wrote a threatening message on another student’s computer.

• With the district already on the “highest alert,” Cloverleaf Schools Superintendent Daryl Kubilus says police have cleared two unsubstantiated online threats reported by other students.

• Stow police search a middle school student’s home after a threat is made on social media. No weapons are found, but in a call to parents, Stow-Munroe Falls Superintendent Tom Bratten says the district and police plan to pursue disciplinary and legal action against the student.

• Sixth- and seventh-graders at St. Mary School, a private elementary school in Akron, notify Principal Pat Nugent of Snapchat and Facebook messages Nugent said went something like: “I’m going to shoot just like the kid in Florida.” Nugent said police couldn’t link the Akron-centric threat to her school or any other in the area.

February 23

• Barberton Superintendent Jeff Ramnytz sends a recorded telephone message to parents at 6:15 a.m. saying that a “concerning text” about a threat allegedly made by a Norton student who attends Barberton schools part-time has been “identified and dealt with” by administrators in Norton.

• Superintendent Jeff Wendorf of North Canton emails parents Thursday night about an “anonymous social media post” threatening violence. Police staff all buildings throughout the day.

• Medina police investigate two threats made Thursday and Friday relating to the Medina school district’s middle schools. The threats are found not to be credible.

• The Medina County Sheriff’s Office quickly responds to a report that a Highland High School student has a gun at the Granger Township school. It’s found to be a toy. The student is placed in the sheriff’s custody and removed from the school.

• Social media helps spread an online threat of violence at a Pennsylvania school that somehow causes waves of panic at two Akron schools. The National Inventors Hall of Fame STEM school downtown brought in extra officers and a metal detector and nearby St. Vincent-St. Mary closed at noon, police said.