Bank requesting financial info during loan repayment period

Hi all,

I currently have a rental property loan with a local bank and I have been paying it for about 2 years without any problems.  I just received a letter from the bank requesting last year's tax returns, personal financial statement, and current rent rolls as part of my portfolio review. They even take the extra step and threaten to default on my rental property if they don't receive this info. 

Is this normal? I'm in excellent standing and I always pay on time.  Business is great but I'm just surprised they need this information, let alone threaten to default unless they receive it.  Thanks in advance.