YANKTON, S.D.(WNAX)- During the energy crisis last week, natural gas prices on the open market spiked, in some cases several thousand percent.

Northwestern Energy spokesman Tom Glanzer says it was a short term heavy surge in demand.

Glanzer says their customers could see some increases in their gas bills.

Glanzer says every retail energy company took some hits from the electric and gas surge.

A huge stretch of the country from Canada to Texas dealt with record low temperatures for most of last week.