diff --git a/src/data/dataset.py b/src/data/dataset.py
index fda42f0..eff50d0 100644
--- a/src/data/dataset.py
+++ b/src/data/dataset.py
@@ -139,6 +139,7 @@ class TerrainDataset(Dataset):
         # * Dataset state
         self.current_file = None
         self.current_blocks = None
+        self.idx_offset = 0
 
     def get_len(self):
         key = list(self.sample_dict.keys())[-1]
@@ -150,6 +151,16 @@ class TerrainDataset(Dataset):
         return self.get_len()
 
     def __getitem__(self, idx):
+        while True:
+            target, mask, file_name = self.__internal_getitem__(idx + self.idx_offset)
+            if not np.all(mask.numpy() == 0):
+                break
+            else:
+                self.idx_offset += 1
+                print(f"Skipped block #{self.idx_offset}")
+        return target, mask, file_name
+
+    def __internal_getitem__(self, idx):
         """
         returns (x, (ox, oy, oz)), y
         """
diff --git a/src/trainer/trainer.py b/src/trainer/trainer.py
index 0288e6f..90a3a87 100644
--- a/src/trainer/trainer.py
+++ b/src/trainer/trainer.py
@@ -19,6 +19,9 @@ class Trainer():
         self.args = args 
         self.iteration = 0
 
+        # Detect anomalies
+        torch.autograd.set_detect_anomaly(True)
+
         # setup data set and data loader
         self.dataloader = create_loader(args)