All Fairfield public schools dismissed students early Friday after police say someone called in anonymous bomb threats, prompting a midday lockdown.

The district also canceled all after-school activities and nighttime sports games.

Police say they immediately sent officers to all 17 of the town's schools.

Neighboring departments also responded.

Police say the threats did not turn out to be credible, but the lockdown and dismissals were standard procedure and part of an abundance of caution.

Police say they first received a 911 call Friday morning about a hostage situation and a pipe bomb. It was apparently unrelated to the schools, but police say they believe it is connected to subsequent calls about the schools. 

The caller reported a bogus address for the hostage situation, according to officials.

A short while later, police say they received another call about explosives and weapons in three schools.

Police say they haven't found anything dangerous in or around the schools.

The investigation is ongoing. Police are asking anyone with information about the threats to call them.