Updated 6.34pm: An area in the centre of Rotorua has been cordoned off after an old bore erupted in a service lane.

The geyser appeared in the lane between Eruera and Amohau Streets.

It is s near the back door of Chopsticks restaurant, and manager Joey Wang said she has never seen anything like it.

"It's coming out with small rocks and hot water, and some muck as well. It's quite dangerous," she said.

It is shooting water two metres into the air.

Police and council staff are at the scene, and council workers will dig to shut down the bore tomorrow.