diff --git a/src/batdetect2/postprocess/__init__.py b/src/batdetect2/postprocess/__init__.py
index 27e45df..b1c0a3a 100644
--- a/src/batdetect2/postprocess/__init__.py
+++ b/src/batdetect2/postprocess/__init__.py
@@ -24,7 +24,6 @@ from batdetect2.preprocess import MAX_FREQ, MIN_FREQ
 from batdetect2.typing import ModelOutput
 from batdetect2.typing.postprocess import (
     BatDetect2Prediction,
-    DetectionsArray,
     DetectionsTensor,
     PostprocessorProtocol,
     RawPrediction,
diff --git a/src/batdetect2/typing/postprocess.py b/src/batdetect2/typing/postprocess.py
index 42afb4a..f75ca81 100644
--- a/src/batdetect2/typing/postprocess.py
+++ b/src/batdetect2/typing/postprocess.py
@@ -96,12 +96,12 @@ class DetectionsTensor(NamedTuple):
 
     def numpy(self) -> DetectionsArray:
         return DetectionsArray(
-            scores=self.scores.detach().numpy(),
-            sizes=self.sizes.detach().numpy(),
-            class_scores=self.class_scores.detach().numpy(),
-            times=self.times.detach().numpy(),
-            frequencies=self.frequencies.detach().numpy(),
-            features=self.features.detach().numpy(),
+            scores=self.scores.detach().cpu().numpy(),
+            sizes=self.sizes.detach().cpu().numpy(),
+            class_scores=self.class_scores.detach().cpu().numpy(),
+            times=self.times.detach().cpu().numpy(),
+            frequencies=self.frequencies.detach().cpu().numpy(),
+            features=self.features.detach().cpu().numpy(),
         )