diff --git a/include/nil/crypto3/hash/block_to_field_elements_wrapper.hpp b/include/nil/crypto3/hash/block_to_field_elements_wrapper.hpp
index 2ef8038..053a020 100644
--- a/include/nil/crypto3/hash/block_to_field_elements_wrapper.hpp
+++ b/include/nil/crypto3/hash/block_to_field_elements_wrapper.hpp
@@ -100,13 +100,12 @@ namespace nil {
                         if (element_filled_) {
                             return;
                         }
-                        value_type field_element = value_type::zero();
+                        field_element_ = value_type::zero();
                         auto tmp_iter = input_container_l_;
                         for (std::size_t i = 0; i < container_elements_per_field_element_ && tmp_iter != input_container_r_; ++i) {
-                            field_element.data <<= input_value_bits_; // TODO: add shift operators to field values
-                            field_element += *tmp_iter++;
+                            field_element_.data <<= input_value_bits_; // TODO: add shift operators to field values
+                            field_element_ += uint64_t(*tmp_iter++);
                         }
-                        field_element_ = field_element;
                         element_filled_ = true;
                     }