Delete Items from Item Branch Master

Can we delete an item from Item Branch Master if the item is associated with an active work order? We are trying to delete some items and receive the following message:

Record Not Available for Deletion

A form level error has occurred.
CAUSE: The item requested for deletion may not be deleted for one
or more of the following reasons:
1. Item Branch record still exists.
2. Cross reference information exists for the item.
3. Item exists as a bill of material component or parent item.
4. Item has an existing routing record.
5. Supplier/Item relationship exists.
6. Price records exist.
7. Item exists on an active sales order.