Удаление блока в чертеже

Public Sub OpenTransactionManager()

            '' Get the current document and database

            Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument

            Dim acCurDb As Database = acDoc.Database



            '' Start a transaction

            Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()


                '' Open the Block table for read

                Dim acBlkTbl As BlockTable

                acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, OpenMode.ForRead)

                '' Open the Block table record Model space for read

                Dim acBlkTblRec As BlockTableRecord

                acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), OpenMode.ForRead)

                '' Step through the Block table record

                For Each acObjId As ObjectId In acBlkTblRec ' Здесь перебираются все объекты

                    acDoc.Editor.WriteMessage(vbLf & "DXF name: " & acObjId.ObjectClass().DxfName)

                    acDoc.Editor.WriteMessage(vbLf & "ObjectID: " & acObjId.ToString())

                    acDoc.Editor.WriteMessage(vbLf & "Handle: " & acObjId.Handle.ToString())

                    acDoc.Editor.WriteMessage(vbLf)
                    If acObjId.ObjectClass().DxfName = "INSERT" Then acObjId
                    необходимо удаление блока 
                Next
                '' Dispose of the transaction

            End Using
        End Sub