Bomb Threat at Columbine High School Triggers 24 School Lockdowns

Update: Officials gave the all-clear

Nearly two-dozen Jefferson County, Colorado, schools were placed on lockout on Dec. 12 after a threat was reported at Columbine High School, the Jefferson County Sheriff's Office told local news outlets. Google Street View

UPDATE at 3 p.m.  ET: The all-clear was given for Jefferson County schools, say local reports.

Reports say that dozens of bomb threats have been emailed to schools, businesses, government officials, and media outlets around the United States on Dec. 12. It’s not clear if Jefferson County schools were included.