Authorities in southern Colorado say a threatening social media post prevented students from walking out of schools to protest gun violence.

The Pueblo Chieftain reports the Florence-Penrose school district went on lockout status early Wednesday morning, and Canon City Schools followed suit shortly after as a precaution.

Canon City Police Sgt. Tim Bell says the student walkout planned nationally to show support for the victims of the Marjory Stoneman-Douglas High School shooting also played a role in enforcing a districtwide lockout.

The walkout and 17 minutes of silence went on at Canon City High School, but instead of going outside, students went to the gym to show support.

KRDO-TV reports two people, including a former Fremont County student, were questioned about the threat.

Students around Colorado joined the nationwide school walkout to protest gun violence, including students at Columbine High School.

About 250 students left Columbine Wednesday and gathered on a soccer field next to the building, not far from the library built in memory of the 13 people killed in the 1999 school shooting.

They released red, white and blue balloons as the names of the 17 people killed at Florida’s Marjory Stoneman Douglas High School, the worst high school shooting since the 1999 massacre at Columbine. Some held homemade signs, including one that said “CO(Loves)FL”.

Marjory Stoneman students spoke to students who walked out at Fairview High School in Boulder. Protesters from some Denver schools continued their demonstration by walking to the state Capitol.