Unable to delete building block group &1

What causes this issue?

You have tried to delete building block group &V1& with the building
blocks it contains. However, certain building blocks in the building
block group are used as an INCLUDE in report templates.

System Response

The building block group &V1& cannot be deleted.

How to fix this error?

Execute a where-used list for the building blocks of the building block
group that cannot be deleted.
If necessary, delete the references to the building blocks in the report
templates.
Once all references to the building blocks in the report templates have
been deleted, you can delete the building blocks and the building block
group.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.