diff --git a/scrapy/downloadermiddlewares/httpcompression.py b/scrapy/downloadermiddlewares/httpcompression.py
index dd32c62de..203dee42d 100644
--- a/scrapy/downloadermiddlewares/httpcompression.py
+++ b/scrapy/downloadermiddlewares/httpcompression.py
@@ -1,6 +1,6 @@
 import zlib
 
-from scrapy.utils.gz import gunzip, is_gzipped
+from scrapy.utils.gz import gunzip
 from scrapy.http import Response, TextResponse
 from scrapy.responsetypes import responsetypes
 from scrapy.exceptions import NotConfigured
diff --git a/scrapy/spiders/sitemap.py b/scrapy/spiders/sitemap.py
index 10af90259..e54001d88 100644
--- a/scrapy/spiders/sitemap.py
+++ b/scrapy/spiders/sitemap.py
@@ -61,10 +61,7 @@ class SitemapSpider(Spider):
         if isinstance(response, XmlResponse):
             return response.body
         elif gzip_magic_number(response):
-            try:
-                return gunzip(response.body)
-            except:
-                pass
+            return gunzip(response.body)
         # actual gzipped sitemap files are decompressed above ;
         # if we are here (response body is not gzipped)
         # and have a response for .xml.gz,