diff --git a/GCDWebServer/Core/GCDWebServerConnection.m b/GCDWebServer/Core/GCDWebServerConnection.m
index 9ec7df2..d6c369e 100644
--- a/GCDWebServer/Core/GCDWebServerConnection.m
+++ b/GCDWebServer/Core/GCDWebServerConnection.m
@@ -759,7 +759,7 @@ static inline NSUInteger _ScanHexNumber(const void* bytes, NSUInteger size) {
 - (void)processRequest:(GCDWebServerRequest*)request completion:(GCDWebServerCompletionBlock)completion {
   GWS_LOG_DEBUG(@"Connection on socket %i processing request \"%@ %@\" with %lu bytes body", _socket, _virtualHEAD ? @"HEAD" : _request.method, _request.path, (unsigned long)_bytesRead);
   @try {
-    _handler.asyncProcessBlock(request, completion);
+    _handler.asyncProcessBlock(request, [completion copy]);
   }
   @catch (NSException* exception) {
     GWS_LOG_EXCEPTION(exception);
diff --git a/GCDWebServer/Core/GCDWebServerResponse.m b/GCDWebServer/Core/GCDWebServerResponse.m
index 740e933..8357ab7 100644
--- a/GCDWebServer/Core/GCDWebServerResponse.m
+++ b/GCDWebServer/Core/GCDWebServerResponse.m
@@ -242,7 +242,7 @@
 
 - (void)performReadDataWithCompletion:(GCDWebServerBodyReaderCompletionBlock)block {
   if ([_reader respondsToSelector:@selector(asyncReadDataWithCompletion:)]) {
-    [_reader asyncReadDataWithCompletion:block];
+    [_reader asyncReadDataWithCompletion:[block copy]];
   } else {
     NSError* error = nil;
     NSData* data = [_reader readData:&error];