diff --git a/lib/hls/hls_parser.js b/lib/hls/hls_parser.js
index 90fac0d304..e78fce4bbf 100644
--- a/lib/hls/hls_parser.js
+++ b/lib/hls/hls_parser.js
@@ -4151,7 +4151,22 @@ shaka.hls.HlsParser = class {
    * @return {?shaka.extern.DrmInfo}
    * @private
    */
-  static identityDrmParser_(drmTag) {
+  static identityDrmParser_(drmTag, mimeType) {
+    if (mimeType == 'video/mp2t') {
+      throw new shaka.util.Error(
+          shaka.util.Error.Severity.CRITICAL,
+          shaka.util.Error.Category.MANIFEST,
+          shaka.util.Error.Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
+    }
+
+    if (shaka.util.Platform.isMediaKeysPolyfilled()) {
+      throw new shaka.util.Error(
+          shaka.util.Error.Severity.CRITICAL,
+          shaka.util.Error.Category.MANIFEST,
+          shaka.util.Error.Code
+              .HLS_MSE_ENCRYPTED_LEGACY_APPLE_MEDIA_KEYS_NOT_SUPPORTED);
+    }
+
     const method = drmTag.getRequiredAttrValue('METHOD');
     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
     if (!VALID_METHODS.includes(method)) {
diff --git a/test/hls/hls_parser_unit.js b/test/hls/hls_parser_unit.js
index 90a81da4ca..8047c07381 100644
--- a/test/hls/hls_parser_unit.js
+++ b/test/hls/hls_parser_unit.js
@@ -4074,6 +4074,34 @@ describe('HlsParser', () => {
       await verifyError(master, media, error, /* onCreateSegmentIndex= */ true);
     });
 
+    it('if SAMPLE-AES encryption with MSE and mp2t content', async () => {
+      const master = [
+        '#EXTM3U\n',
+        '#EXT-X-STREAM-INF:BANDWIDTH=200,CODECS="avc1",',
+        'RESOLUTION=960x540,FRAME-RATE=60\n',
+        'video\n',
+      ].join('');
+
+      const media = [
+        '#EXTM3U\n',
+        '#EXT-X-TARGETDURATION:6\n',
+        '#EXT-X-PLAYLIST-TYPE:VOD\n',
+        '#EXT-X-KEY:METHOD=SAMPLE-AES,',
+        'URI="fake",\n',
+        '#EXTINF:5,\n',
+        '#EXT-X-BYTERANGE:121090@616\n',
+        'main.ts',
+      ].join('');
+
+      const error = new shaka.util.Error(
+          shaka.util.Error.Severity.CRITICAL,
+          shaka.util.Error.Category.MANIFEST,
+          Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
+
+      await verifyError(master, media, error, /* onCreateSegmentIndex= */ true);
+    });
+
+
     describe('if required tags are missing', () => {
       /**
        * @param {string} master