Chaos unfolded in a Mountain View neighborhood in the wee hours of Saturday morning after a resident reported feeling sick from a suspicious white powder that came out of an envelope, police said. The Mountain View Fire Department was called to a multi-family residence in the 2700 block of W. El Camino Real at 12:49 a.m. following a 9-1-1 call about an opened envelope that contained a solitary Scrabble tile and an unknown white residue.

Before firefighters could arrive, the Mountain View Police Department had already ushered the building's tenants into the lobby for safety and placed the ominous envelope outside. According to a news release, the busy Del Medio Avenue and the number three lane of W. El Camino Real were shut down for about two hours as the hazmat scare was tackled.

With a battalion chief and multiple engines on site, the Mountain View Fire Department's HazMat unit swooped in to establish isolation zones. The team, outfitted with specialized gear, conducted tests on the substance. Initially unclear results eventually pointed to the presence of ephedrine, an over-the-counter medication, debunking fears of a more sinister substance.

The scare sparked a large-scale response, featuring one battalion chief, various engines including Engine 51 and Engine 53, Rescue 51, Truck 51, and HazMat Unit 55. One person who reported feeling nauseous received medical attention right on the scene but wasn't carted off to the hospital. Once the all-clear was given, residents got the green light to head back to their homes. The City of Mountain View Fire Department reported that their HazMat Unit 55 holds a Type 2 certification from the California Governor's Office of Emergency Services, signifying their readiness to handle a bevy of industrial chemical incidents.

The incident, while alarming, turned out to be a false alarm with no hazardous materials detected. The Mountain View Fire Department noted that quick and cautious measures are essential in these situations to ensure public safety.