"The case has been confirmed," Feng Shaoming, spokesman for the Guangdong Centre for Disease Control, said.
"Our experts at the Centre for Disease Control have made many tests and they are all positive."
Three experts from the World Health Organisation (WHO) were in the provincial capital of Guangzhou on Tuesday and were going over the test results, Feng said.
He added that the case would not be officially upgraded to a confirmed case until the Ministry of Health made a formal announcement.
"I don't know when they will, it is up to them, but our experts here have confirmed it," Feng said.
Wang Maowu, director of disease control at the national-level Chinese Centre for Disease Control, said an official statement was likely to be issued on Wednesday.
"Our work still needs to be done," Wang said.
WHO continues tests
Roy Wadia, WHO's Beijing-based spokesman, said no official confirmation of the case had come out of the Ministry of Health and the WHO was trying to contact their ministerial counterpart.
"We are trying to confirm with the Ministry of Health, we are also trying to contact our team in Guangzhou to get clarification," Wadia said.
"We are trying to confirm with the Ministry of Health, we are also trying to contact our team in Guangzhou to get clarification"
"So far we have no official word ourselves."
China's health ministry had on Saturday announced the discovery of a suspected case of SARS in a 32-year-old man in the Guangdong provincial capital of Guangzhou, near where the virus was first detected last year.
The freelance journalist, identified only as Luo, developed a fever on 16 December and was admitted to hospital with pneumonia in his right lung on 20 December.
No fresh cases
None of the 42 people quarantined after having close contact with him had shown any SARS symptoms, such as a high temperature or breathing difficulties.
SARS emerged in Guangdong in late 2002 and travellers spread it to nearly 30 countries.
A total of about 8000 infections were logged around the world, spurring mass panic and forcing people to cancel trips and shun crowded places.
Two recent confirmed cases in Singapore and Taiwan were blamed on mishaps in medical research laboratories.
The Singapore patient recovered and was discharged, while the Taiwan patient is expected to be released soon.