
Emergency services were called to a fire at the three-toilet block at 4.41am.
An Oamaru police spokeswoman said the middle toilet of the block had been set on fire.
The hand basin, hand dryer and toilet roll dispensers had been ripped from the wall.
"There’s superficial smoke damage to the toilet block, but extensive damage to the dryer and everything like that," the spokeswoman said.
There was damage throughout the other toilets as well, but the middle toilet received the main vandalism.

A Waitaki District Council Facebook post said it hoped to have one toilet open for the weekend, and would look at portaloos too.
Police would like to hear from anybody who had any information about the incident.
Overnight, the Awamoa Park men’s toilet block also had the hand basin ripped from the wall, and someone drove through the fence at the Phoenix Mill Water Wheel, in Old Mill Rd.