Police are investigating after man wearing Trump T-shirt puts up anti-Semitic posters at Queenstown tertiary institute.

Police have made contact with two men after anti-Semitic posters were placed around Queenstown Resort College.

A security camera image posted earlier on the Southern District Police Facebook page shows two men – one in dark glasses, camo pants and wearing a "Trump" t-shirt – entering the tertiary institute last week. The photo has since been removed from the police Facebook page.

An anonymous email directed Stuff to a Facebook page showing photos of the posters containing Nazi swastikas and anti-Jewish slogans. The photos have since been taken down.

The page's spokesman, Adam Holland, said he was waiting for police to get in contact again.

READ MORE: Prominent Kiwis pen open letter saying free speech is under threat in NZ universities

It was "absolutely ridiculous" police were looking into the matter, he said.

"This looks like freedom of speech not hate speech."

Senior Sergeant Paula Enoka said the matter would be followed up on Tuesday.

The two men had since contacted police and the post had been taken down, a police spokeswoman said.

Information about possible charges would not be available until the men were spoken to again, she said.

Queenstown Resort College chief executive Charlie Phillips said two men put the posters up and, once alerted to them, staff took them down and contacted police.

"It's unrelated to anything at the college.

"We didn't recognise the people," Phillips said.

The incident comes after an open letter signed by 27 prominent New Zealander's warned freedom of speech was under threat in the country's universities.

Anyone with information is asked to call Queenstown police on 03 441 1600 or can provide information anonymously by calling Crimestoppers on 0800 555 111.