(NBC News) Rescue crews in Colorado, mounting what was called the largest civilian helicopter mission since Hurricane Katrina, waited for clear weather Monday in hopes of reaching hundreds of people trapped by catastrophic floods.
Authorities instructed the stranded to set flares, wave light-colored sheets from the roofs of houses and use mirrors to reflect the sunlight and attract the attention of the teams sent to save them.
The floods have killed at least five people, wrecked more than 17,000 homes and left more than 1,200 people unaccounted for. Phone service, cell and landline, was out across much of the disaster zone, blocking authorities from knowing the full human toll.
Copyright 2013 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.