Auckland Transport staff are in isolation after passengers spat at them.
On a train this morning, a woman spat at three transport officers.
"A couple were joy-riding on our trains and were told to get off," AT chief executive Shane Ellison said.
"As they were being escorted from the train, a female spat at three of our staff. Two men and a woman have had to be stood down as a result and have gone into isolation. This behaviour is totally unacceptable."
He said the spitting was caught on CCTV and police have the footage.
Ellison said a security guard working for AT was spat at on Wednesday night.
"Again, the police were called.
"We have staff working day and night to keep public transport operating and it's distressing when they come under attack from members of the public.
"Our staff and contractors are out there in all weathers ensuring that essential workers can get to their jobs and we cannot tolerate this sort of behaviour. We are working with the police to ensure that our staff can do their job without being assaulted.
"It's quite disturbing that a few people are acting like idiots, we've been getting some great feedback about the efforts that we have been making to get people around the city in these tough times but to have incidents like this is quite upsetting."
During alert level 4 Auckland Transport is maintaining a weekend service on all public transport with physical distancing. Public transport is free and is only to be used by essential workers and people going to medical appointments or doing shopping.
Mayor Phil Goff described the spitting as dangerous.
"That sort of behaviour is disgusting at any time, but with Covid-19 it's also dangerous. The individuals should face the full penalties under the law and I have no doubt that the police will be taking this matter very seriously.
"Our thanks go to our essential transport staff and all of the key workers across Auckland and New Zealand who are working tirelessly at some risk to their personal safety to ensure that the services we all rely on can continue to function throughout the lockdown."