South Australia is lifting its six-day lockdown days early, after revealing it was imposed based on the lies of a pizza bar employee.

Premier Steven Marshall said 14,400 people had been tested across the state on Thursday as it tried to quell the “dangerous” Parafield cluster that sparked the lockdown.

The outbreak grew by three on Friday, with new cases in people who are all among the thousands in quarantine. There are also 44 more suspected infections.

But a clearly angry Premier also hit out at a worker at the pizza bar central to the outbreak that has infected 25 people across Adelaide’s north.

“Their story didn’t add up. We pursued them. We now know that they lied,” he said.

The man works as a security guard at a city medi-hotel. SA Police Commissioner Grant Stephens said he claimed to have bought a pizza from the Woodville restaurant, but was actually a worker there – increasing his exposure to the coronavirus.

“That clearly changes the circumstances and had this person been truthful to the contact tracing teams, we would not have gone into a six-day lock down,” he said.

Earlier this week, SA health authorities issued an alert for the Woodville pizza bar that included anyone who had even bought takeaway from it.

Mr Marshall said the worker had deliberately misled contact tracers.

“To say I am fuming about the actions of this individual is an absolute understatement. The selfish actions of this individual have put our whole state in a very difficult situation,” he said.

“His actions have affected businesses, individuals, family groups and is completely and utterly unacceptable.”

Mr Stephens said South Australians would immediately be able to resume exercising outside their homes in family groups. From midnight Saturday, the state will begin to return to the restrictions it had earlier this week.

Schools and gyms will be able to reopen, and most people will be able to return to work as stay-at-home orders are lifted.

Thousands have turned out for virus testing in Adelaide this week, after news of the outbreak emerged.

Masks remain strongly encouraged for South Australians, but are not compulsory.

“Thanks to the work of South Australia police, we have been able to uncover this lie and lift those restrictions as quickly as we can,” Mr Marshall said.

“What we have learnt from today’s revelation is there is a whole group of other people, other associates, that we need to trace down and put back into quarantine as quickly as we possibly can. And that work will go ahead, immediately, with the added sort of expertise coming from as a police.”

Mr Marshall said the Parafield cluster remained dangerous.

Mr Stephens said the worker would not be fined because there was no penalty for failing to tell the truth.

SA’s chief public health officer Nicola Spurrier said authorities expected to find more cases in the Parafield outbreak, despite Friday’s revelations.

“That is because we got so early in the beginning of this cluster, and how people put in quarantine, and when we first tested them, they had not actually become positive,” she said.

“But we will be expecting that to happen now over the next couple of days.”