Is it the same property you discuss in this thread? That sounds like a rental. If so, yes, there will be taxes on the forgiven debt, and, as Richard points out, its ordinary income, not capital gains.
The exception Richard mentions is for forgiven debt on a primary residence, and only for acquisition or improvement debt. It you did a cash out refinance or a HELOC and used the money for something other than improvements to the property, the exception doesn't apply.
I asked some questions in that other post that are relevant here. What's your personal financial situation? There's another way to avoid these taxes, and that's to show insolvency. But if you have income and assets, you won't be able to do that. But if you have income and assets, you're not going to be able to do a short sale to start with.