Delete Multipal Record Query ?

I am try to this things,

 When i delete state also delete this state city delete.

my query

DELETE FROM ab
FROM         City AS ab INNER JOIN
                      State AS b ON ab.state_id = b.state_id CROSS JOIN
                      ab
WHERE     (ab.state_id =
                          (SELECT     state_id
                            FROM          State
                            WHERE      (state_name = @state_name)))

My city table

city_id,city_name,state_id

Error Message : Invalid object name 'ab'