diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index 1837995d5..e72361df2 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/src/pocketmine/entity/Entity.php
@@ -494,7 +494,10 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$pos = $this->namedtag->getListTag("Pos")->getAllValues();
 
 		$this->chunk = $level->getChunk(((int) $pos[0]) >> 4, ((int) $pos[2]) >> 4, true);
-		assert($this->chunk !== null);
+		if($this->chunk === null){
+			throw new \InvalidStateException("Cannot create entities in unloaded chunks");
+		}
+
 		$this->setLevel($level);
 		$this->server = $level->getServer();
 
diff --git a/src/pocketmine/tile/Tile.php b/src/pocketmine/tile/Tile.php
index ec28b869e..19c706c69 100644
--- a/src/pocketmine/tile/Tile.php
+++ b/src/pocketmine/tile/Tile.php
@@ -146,7 +146,9 @@ abstract class Tile extends Position{
 		$this->server = $level->getServer();
 		$this->setLevel($level);
 		$this->chunk = $level->getChunk($this->namedtag->getInt(self::TAG_X) >> 4, $this->namedtag->getInt(self::TAG_Z) >> 4, false);
-		assert($this->chunk !== null);
+		if($this->chunk === null){
+			throw new \InvalidStateException("Cannot create tiles in unloaded chunks");
+		}
 
 		$this->name = "";
 		$this->id = Tile::$tileCount++;