A Hudson student was issued a citation Thursday after a school-bus conversation that concerned at least one other classmate.

Hudson School District Superintendent Nick Ouellette emailed district families Thursday evening to say the incident was investigated by police and deemed not to be a threat.

"However, because of the fear and anxiety statements like this make, the student was issued a citation," Ouellette wrote.

He told families there is a heightened police presence in the district on Friday.

District Assistant Director of Community Relations Tracy Habisch-Ahlin said Friday that student privacy laws prevented disclosure of what building the student attends, but said it occurred "on one of our secondary school buses." High schools are generally synonymous with secondary education.

According to Ouellette's letter: Two students were discussing Wednesday's walk-out at Hudson High School, which was part of a national student-led effort in recognition of the Parkland, Florida, school shooting's one-month anniversary.

Referencing the walk-out, one of the students on the bus mentioned "how easy it would have been to 'shoot them up.'" The comment prompted the other student to say they needed to stop talking about the matter.

Another student on the bus overheard the conversation and told a parent, who in turn immediately contacted the Safeway Bus Co. and the district. Hudson police investigated the matter, concluding it wasn't a credible threat.

Hudson police didn't immediately return a call seeking information about the investigation.

Habisch-Ahlin said the student who passed along the information to parents did exactly what the district wants - to report disturbing situations when they arise.

"We want to restate the importance of children who hear things, or see things on social media; to say something to a teacher, administrator, or adult immediately," Ouellette wrote. "Parents should let their children know threats to harm others may be considered a felony level offense and, in addition to criminal charges, may result in a school expulsion."

Thursday's incident was the latest in what Habisch-Ahlin said has been a challenging week for the district, which responded on Tuesday to a middle school threat that resulted in criminal charges against a student.

However, Habisch-Ahlin said Hudson schools saw "a great response from our students and staff, and the police department in helping us."

She acknowledged some families may be concerned the district hasn't done "everything right" this week, but pointed out "we've had kids safe all week and we've kept school going all week."