An unknown person or persons – dubbed ‘The Midnight Knitter’ by West Cape May residents – is covering tree branches and lamp poles with little sweaters under cover of darkness.

Mayor Pam Kaithern says police are looking into the knitted graffiti, which is technically against the law, as it is being done on public property without permission.

However, the mayor and many residents admit they’re delighted by the woolly rainbow of colours that has popped up.

‘We don’t know who it is. Technically, they shouldn’t be doing it. The police are asking about it, but it’s fun and it’s a mystery,’ Kaithern told local newspaper The Press of Atlantic City.

And she added that she’s not even that keen for police to get to the bottom of the affair. ‘Lets’ keep it a mystery,’ she said.

The knitter even has a website, a Facebook page and a MySpace, under the name of ‘Salty Knits’, where they describe themselves as ‘Knitters that got sick of knitting kitten mittens.’

The Facebook page is filled with overwhelmingly positive comments about the undercover needlework. One said: ‘Don’t give in to requests for you all to identify yourselves . . . just keep doing what you’re doing. Mystery is nice.’