Police have said another quad bike has been stolen from a farm in the area, the second in the past week and one of several in recent weeks.
The latest theft took place on Thursday between 8pm and 10pm in the Berriew area, although police haven't said exactly where.
It follows the theft of a quad bike in Manafon last week.
Police have urged farmers and landowners to be vigilant and anyone who sees anything or anyone acting suspiciously to report it to them.
Anyone who has information about the thefts can call Newtown Police on 101.