diff --git a/sherpa-onnx/csrc/offline-speaker-diarization-pyannote-impl.h b/sherpa-onnx/csrc/offline-speaker-diarization-pyannote-impl.h
index e8228d47b..8573c7494 100644
--- a/sherpa-onnx/csrc/offline-speaker-diarization-pyannote-impl.h
+++ b/sherpa-onnx/csrc/offline-speaker-diarization-pyannote-impl.h
@@ -160,6 +160,11 @@ class OfflineSpeakerDiarizationPyannoteImpl
     std::vector<int32_t> cluster_labels = clustering_->Cluster(
         &embeddings(0, 0), embeddings.rows(), embeddings.cols());
 
+    if (cluster_labels.empty()) {
+      SHERPA_ONNX_LOGE("No speakers found in the audio samples");
+      return {};
+    }
+
     int32_t max_cluster_index =
         *std::max_element(cluster_labels.begin(), cluster_labels.end());