diff --git a/src/coarse/coarse.c b/src/coarse/coarse.c
index 956e54857e..19798466e1 100644
--- a/src/coarse/coarse.c
+++ b/src/coarse/coarse.c
@@ -1170,10 +1170,13 @@ umf_result_t coarse_free(coarse_t *coarse, void *ptr, size_t bytes) {
     }
 
     block_t *block = get_node_block(node);
-    assert(block->used);
+    if (!block->used) {
+        LOG_ERR("double free");
+        utils_mutex_unlock(&coarse->lock);
+        return UMF_RESULT_ERROR_INVALID_ARGUMENT;
+    }
 
     if (bytes > 0 && bytes != block->size) {
-        // wrong size of allocation
         LOG_ERR("wrong size of allocation");
         utils_mutex_unlock(&coarse->lock);
         return UMF_RESULT_ERROR_INVALID_ARGUMENT;
diff --git a/test/coarse_lib.cpp b/test/coarse_lib.cpp
index a1aec224ae..c2e1f9c856 100644
--- a/test/coarse_lib.cpp
+++ b/test/coarse_lib.cpp
@@ -160,6 +160,13 @@ TEST_P(CoarseWithMemoryStrategyTest, coarseTest_basic_provider) {
     ASSERT_EQ(coarse_get_stats(ch).alloc_size, alloc_size);
     ASSERT_EQ(coarse_get_stats(ch).num_all_blocks, 1);
 
+    // test double free
+    umf_result = coarse_free(ch, ptr, 2 * MB);
+    ASSERT_EQ(umf_result, UMF_RESULT_ERROR_INVALID_ARGUMENT);
+    ASSERT_EQ(coarse_get_stats(ch).used_size, 0);
+    ASSERT_EQ(coarse_get_stats(ch).alloc_size, alloc_size);
+    ASSERT_EQ(coarse_get_stats(ch).num_all_blocks, 1);
+
     coarse_delete(ch);
     umfMemoryProviderDestroy(malloc_memory_provider);
 }
@@ -202,6 +209,13 @@ TEST_P(CoarseWithMemoryStrategyTest, coarseTest_basic_fixed_memory) {
     ASSERT_EQ(coarse_get_stats(ch).alloc_size, buff_size);
     ASSERT_EQ(coarse_get_stats(ch).num_all_blocks, 1);
 
+    // test double free
+    umf_result = coarse_free(ch, ptr, 2 * MB);
+    ASSERT_EQ(umf_result, UMF_RESULT_ERROR_INVALID_ARGUMENT);
+    ASSERT_EQ(coarse_get_stats(ch).used_size, 0);
+    ASSERT_EQ(coarse_get_stats(ch).alloc_size, buff_size);
+    ASSERT_EQ(coarse_get_stats(ch).num_all_blocks, 1);
+
     coarse_delete(ch);
 }