diff --git a/CHANGES.md b/CHANGES.md
index 718e04c1..7d2f215c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -11,6 +11,7 @@ There are likely to be descriptions etc outside of the list below, but new query
 |---------------------------------------------------------------------------------------------------------------------|--------------------------------------------------|---------------------------------------------------|----------------------------------------------------|-------------------------------------------------|-------------------------------------------|
 | [#339](https://github.com/ethereum/beacon-APIs/pull/339) `POST /eth/v3/beacon/blocks` added                         |                                                  |                                                   |                                                    |                                                 |                                           |
 | [#350](https://github.com/ethereum/beacon-APIs/pull/350) `blob_sidecar EVENT` added                                 |                                                  |                                                   |                                                    |                                                 |                                           |
+| [#366](https://github.com/ethereum/beacon-APIs/pull/366) `proposer_slashing, attester_slashing EVENT` added         |                                                  |                                                   |                                                    |                                                 |                                           |
 | [#367](https://github.com/ethereum/beacon-APIs/pull/367) `POST /eth/v1/beacon/states/{state_id}/validators`         |                                                  |                                                   |                                                    |                                                 |                                           |
 | [#367](https://github.com/ethereum/beacon-APIs/pull/367) `POST /eth/v1/beacon/states/{state_id}/validator_balances` |                                                  |                                                   |                                                    |                                                 |                                           |
 
diff --git a/apis/eventstream/index.yaml b/apis/eventstream/index.yaml
index 63e804c8..682972db 100644
--- a/apis/eventstream/index.yaml
+++ b/apis/eventstream/index.yaml
@@ -27,6 +27,8 @@ get:
             - attestation
             - voluntary_exit
             - bls_to_execution_change
+            - proposer_slashing
+            - attester_slashing
             - finalized_checkpoint
             - chain_reorg
             - contribution_and_proof
@@ -63,6 +65,16 @@ get:
               value: |
                 event: voluntary_exit
                 data: {"message":{"epoch":"1", "validator_index":"1"}, "signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}
+            proposer_slashing:
+              description: The node has received a ProposerSlashing (from P2P or API) that passes validation rules of the `proposer_slashing` topic
+              value: |
+                event: proposer_slashing
+                data: {"signed_header_1":{"message":{"slot":"0","proposer_index":"0","parent_root":"0x0000000000000000000000000000000000000000000000000000000000000000","state_root":"0x0000000000000000000000000000000000000000000000000000000000000000","body_root":"0x0000000000000000000000000000000000000000000000000000000000000000"},"signature":"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"},"signed_header_2":{"message":{"slot":"0","proposer_index":"0","parent_root":"0x0000000000000000000000000000000000000000000000000000000000000000","state_root":"0x0000000000000000000000000000000000000000000000000000000000000000","body_root":"0x0000000000000000000000000000000000000000000000000000000000000000"},"signature":"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"}}
+            attester_slashing:
+              description: The node has received an AttesterSlashing (from P2P or API) that passes validation rules of the `attester_slashing` topic
+              value: |
+                event: attester_slashing
+                data: {"attestation_1":{"attesting_indices":["0", "1"],"data":{"slot":"0","index":"0","beacon_block_root":"0x0000000000000000000000000000000000000000000000000000000000000000","source":{"epoch":"0","root":"0x0000000000000000000000000000000000000000000000000000000000000000"},"target":{"epoch":"0","root":"0x0000000000000000000000000000000000000000000000000000000000000000"}},"signature":"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"},"attestation_2":{"attesting_indices":["0", "1"],"data":{"slot":"0","index":"0","beacon_block_root":"0x0000000000000000000000000000000000000000000000000000000000000000","source":{"epoch":"0","root":"0x0000000000000000000000000000000000000000000000000000000000000000"},"target":{"epoch":"0","root":"0x0000000000000000000000000000000000000000000000000000000000000000"}},"signature":"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"}}
             bls_to_execution_change:
               description: The node has received a BLS to execution change (from P2P or API)
               value: |