Schools in the metro area have told 9NEWS they are aware of rumors. None have told 9NEWS of any credible threats.

"School resource officers have found numerous inappropriate comments dealing with school violence on students' Facebook pages and Twitter accounts," Aurora Police Department spokesman Frank Fania said Wednesday.

He too said none of the threats have been credible.

Fania said the rumors aren't confined to one school or district.

"It's occuring in the City of Aurora and elsewhere," he said.

Police are following up on concerns when they are reported by the schools, he said.

Some of the comments also deal with talk of the Mayan doomsday prediction.

"It's not just related to school violence, but they also reference the world ending," Fania said.