Colorado's Pseudo-Terror Spree

Things to do in Denver when you're bored?

A letter with a granular substance was sent to the Colorado History Museum on Wednesday morning, mimicking four other letters sent to state offices this week, Denver fire Lt. Phil Champagne said.

The substance found inside the envelope was probably sugar or an artificial sweetener, he said.

About 100 employees at the museum, 1300 Broadway, left the building on their own before firefighters arrived to examine the substance.

The letter also contained threats, as did the four letters sent to three downtown offices and the Colorado Department of Agriculture building in Lakewood.