6. Where the Secretary of State has reasonable cause to believe that a relevant low power device is causing undue interference with any wireless telegraphy, any person who is in possession or control of that device shall on the demand in that behalf of any person authorised for such purpose by the Secretary of State (“the authorised person”) forthwith cause the use of that device to –
(a)cease; or
(b)be restricted in the manner specified by the authorised person.