I don’t know if you want to delete or replace,. so uncomment the command you want.
tell application "BBEdit"
activate
tell window 1
select (lines 10 thru 15)
(* Replace...depending on what the line endings of the document are... use \\r or \\n *)
--replace "^.*\\r" using "<p>\\r" searching in selection options {search mode:grep, extend selection:false}
(* Delete *)
--delete selection
end tell
save document 1
end tell