WOODBURY - Some Nassau residents are seeing higher tax bills due to an expensive error.

John and Marie Zabielski, of Sea Cliff, say they noticed a $1,000 fee for fire and water services in Massapequa this month.

Tax officials in Oyster Bay say they don't yet know the extent of the issue.

"The only reason we found this particular instance out is because it was brought to our attention," says James Stefanich, Oyster Bay town's receiver of taxes.

Town officials say "multiple instances" of errors on tax bills have mostly occurred in Lido Beach and Sea Cliff.

County officials, who are in charge of providing tax assessment information to the individual towns, blamed a computer glitch.