Strong leads are developing, but the investigation will likely remain active through at least the rest of the week. 
That word from Wathena Chief of Police Raymond Hall, following Wedneday's bomb threat at Riverside School district's west campus, in Wathena.
Hall, and investigators, Thursday morning were at the school, addressing the situation(Play Audio :21 seconds)
The investigation follows the “credible threat” discovered around 11:30 Wednesday morning(Play Audio :14 seconds)
The threat forced the evacuation of students, and the cancellation of classes, as local investigators were joined by the Kansas Highway Patrol, and that agency's bomb sniffing dog, as school facilities were searched.
No explosive device was reportedly found during the search, which lasted well into the late afternoon Wednesday.