diff --git a/app/controllers/steps_controller.rb b/app/controllers/steps_controller.rb
index b0d46a564..aa658bd7d 100644
--- a/app/controllers/steps_controller.rb
+++ b/app/controllers/steps_controller.rb
@@ -227,29 +227,38 @@ class StepsController < ApplicationController
   end
 
   def destroy
-    # Update position on other steps of this module
-    @protocol.steps.where("position > ?", @step.position).each do |step|
-      step.position = step.position - 1
-      step.save
+    if @step.can_destroy?
+      # Update position on other steps of this module
+      @protocol.steps.where('position > ?', @step.position).each do |step|
+        step.position = step.position - 1
+        step.save
+      end
+
+      # Calculate space taken by this step
+      org = @protocol.organization
+      previous_size = @step.space_taken
+
+      # Destroy the step
+      @step.destroy(current_user)
+
+      # Release space taken by the step
+      org.release_space(previous_size)
+      org.save
+
+      # Update protocol timestamp
+      update_protocol_ts(@step)
+
+      flash[:success] = t(
+        'protocols.steps.destroy.success_flash',
+        step: (@step.position + 1).to_s
+      )
+    else
+      flash[:error] = t(
+        'protocols.steps.destroy.error_flash',
+        step: (@step.position + 1).to_s
+      )
     end
 
-    # Calculate space taken by this step
-    org = @protocol.organization
-    previous_size = @step.space_taken
-
-    # Destroy the step
-    @step.destroy(current_user)
-
-    # Release space taken by the step
-    org.release_space(previous_size)
-    org.save
-
-    # Update protocol timestamp
-    update_protocol_ts(@step)
-
-    flash[:success] = t(
-      "protocols.steps.destroy.success_flash",
-      step: (@step.position + 1).to_s)
     if @protocol.in_module?
       redirect_to protocols_my_module_path(@step.my_module)
     else
diff --git a/app/models/step.rb b/app/models/step.rb
index 21323b6df..2ade330ae 100644
--- a/app/models/step.rb
+++ b/app/models/step.rb
@@ -82,6 +82,10 @@ class Step < ActiveRecord::Base
     super()
   end
 
+  def can_destroy?
+    !assets.map(&:locked?).any?
+  end
+
   def my_module
     protocol.present? ? protocol.my_module : nil
   end
diff --git a/app/views/steps/_step.html.erb b/app/views/steps/_step.html.erb
index 2dc3a5e68..07d5ce2e1 100644
--- a/app/views/steps/_step.html.erb
+++ b/app/views/steps/_step.html.erb
@@ -16,7 +16,7 @@
             <span class="glyphicon glyphicon-edit">
           </a>
         <% end %>
-        <% if can_delete_step_in_protocol(@protocol) %>
+        <% if can_delete_step_in_protocol(@protocol) && step.can_destroy? %>
           <%= link_to(step_path(step), title: t("protocols.steps.options.delete_title"), method: "delete", class: "btn btn-link",
             data: {action: "delete-step", confirm: t("protocols.steps.destroy.confirm", step: step.name)}) do %>
             <span class="glyphicon glyphicon-trash">
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 5eaf22013..da60b9203 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -1444,6 +1444,7 @@ en:
       destroy:
         confirm: "Are you sure you want to delete step %{step}?"
         success_flash: "Step %{step} successfully deleted."
+        error_flash: "Step %{step} couldn't be deleted. One or more files are locked."
     edit:
       head_title: "Edit protocol"
     no_keywords: "No keywords"