CHICAGO (CBS) — Volunteers have spent the day building winter shelters for feral cats in Chicago, reports WBBM’s Mike Krauser reports.

At the PAWS Chicago Medical Center on the 3500 block of West 26th Street, volunteers were hard at work turning plastic tubs into shelters using Styrofoam insulation and hay.

“We are hosting our first ever cold weather shelter build for outdoor cats that live in Chicago,” said Karina Holmes, PAWS director of operations. “We are delivering them first to the community where we have had an active TNR process and TNR stands for trap, neuter, return, so actually we’re working in the Englewood community for the past 18 months where we trapped over a thousand cats.”

Holmes says from one cat over a ten-year lifetime of having litters, there could be 700,000 cats. She invites volunteers and donations. For more information, visit www.pawschicago.org and the PAWS Facebook page.