Cloud Vision API Landmark response "Internal server error. Unexpected feature response."

I'm using Google Cloud Vision API for landmark detection, and for some images I always get "Internal server error. Unexpected feature response." without any additional info. HTTP status code is 200. I've tried changing image size but didn't help. I'm also getting this response for images that are returning fine when I set maxResults parameter to something bigger than 1.

URL for request: https://vision.googleapis.com/v1/images:annotate

Response:

{
    responses =     (
                {
            error =             {
                code = 13;
                message = "Internal server error. Unexpected feature response.";
            };
        }
    );
}

It appears an on-going issue, There is an Issue tracker filed for this with the exact error:

Cloud Vision now with "LANDMARK_DETECTION" feature returns {"error":{"code":13,"message":"Internal server error. Unexpected feature response."}}

You can track the progress of the issue here, I would also suggest to contact support/ create a case for Google to investigate your case further: https://cloud.google.com/contact