Let's take the first few characters of your json
"{ \"poi\":[\u000d\u000a
^ ^ ^ ^^^^^^
| | | |-----------> not sure about all this
| | -------------------> not acceptable in json
| ------------------------> not acceptable in json
---------------------------> not acceptable in json
What you get back from that website is not valid root json. Fix your source if you have control over it. Or use the String utility methods to replace those characters.