Police are asking people to be vigilant in reporting suspicious behaviour immediately.
Constable Andrew Holdaway, of Blenheim, said anyone who sees a person hanging around acting suspiciously should call 111.
A house in Picton was burgled between Tuesday evening and Wednesday morning, he said.
Outdoor furniture was also stolen from a Blenheim property. Chairs were taken from the front porch of a house in Alfred St overnight on Sunday, Mr Holdaway said.
- The Marlborough Express