Add new field to a nested object

Elasticsearch 2.3.3

I can't add a new field into an existing document via update API.
How can I add it?

Below you can see Elasticsearch Python API script for the document update. The update query is assigned to the query variable.

import pdb, json
from elasticsearch import Elasticsearch
from settings import *

def main():
    es = Elasticsearch(hosts = [{'host': es_hosts, 'port': es_port}], timeout = 60)

    query = {
        "script" : "ctx._source.Demographic_Details[0].Match = 1"
    }

    result = es.update(index = es_index, \
            id = "506GBBO25953J", doc_type = "User", body = query, refresh = "true")

    print(json.dumps(result, indent = 2))

if __name__ == "__main__":
    main()

I use nested objects. There are no problems with updating not nested fields.

A piece of Elasticsearch document:

{
  "hits": {
    "hits": [
      {
        "_score": 0.0, 
        "_type": "User", 
        "_id": "506GBBO25953J", 
        "_source": {
          ...
          "Demographic_Details": [
            {
              "comment": null,
              ... 
              "Occupation": ""
            }
          ], 
          ...
        }, 
        "_index": "logic"
      }
    ], 
    "total": 1, 
    "max_score": 0.0
  }, 
  ...
}

A piece of Elasticsearch mappings:

{
  "logic" : {
    "mappings" : {
      "Patient" : {
        "_all" : {
          "analyzer" : "edge_ngram_analyzer",
          "search_analyzer" : "keyword_analyzer"
        },
        "properties" : {
          "ID" : {
            "type" : "string"
          },
          "Demographic_Details" : {
            "type" : "nested",
            "properties" : {
              ...
              "Occupation" : {
                "type" : "string",
                "analyzer" : "edge_ngram_analyzer",
                "search_analyzer" : "keyword_analyzer"
              },
              "comment" : {
                "type" : "string",
                "analyzer" : "edge_ngram_analyzer",
                "search_analyzer" : "keyword_analyzer"
              },
              "Match" : {
                "type" : "long"
              }
            }
          },
          ...
        }
      }
    }
  }
}

The following error appears after update run:

Traceback (most recent call last):
  File "./update.py", line 26, in <module>
    main()
  File "./update.py", line 21, in main
    id = "506GBBO25953J", doc_type = "User", body = query, refresh = "true")
  File "/home/trex/Development/Sirius/new/project0/project0-venv/local/lib/python2.7/site-packages/elasticsearch/client/utils.py", line 69, in _wrapped
    return func(*args, params=params, **kwargs)
  File "/home/trex/Development/Sirius/new/project0/project0-venv/local/lib/python2.7/site-packages/elasticsearch/client/__init__.py", line 460, in update
    doc_type, id, '_update'), params=params, body=body)
  File "/home/trex/Development/Sirius/new/project0/project0-venv/local/lib/python2.7/site-packages/elasticsearch/transport.py", line 329, in perform_request
    status, headers, data = connection.perform_request(method, url, params, body, ignore=ignore, timeout=timeout)
  File "/home/trex/Development/Sirius/new/project0/project0-venv/local/lib/python2.7/site-packages/elasticsearch/connection/http_urllib3.py", line 109, in perform_request
    self._raise_error(response.status, raw_data)
  File "/home/trex/Development/Sirius/new/project0/project0-venv/local/lib/python2.7/site-packages/elasticsearch/connection/base.py", line 108, in _raise_error
    raise HTTP_EXCEPTIONS.get(status_code, TransportError)(status_code, error_message, additional_info)
elasticsearch.exceptions.RequestError: TransportError(400, u'illegal_argument_exception', u'[es2][192.168.1.10:9300][indices:data/write/update[s]]')