A representative of Queensland Health said it was believed most of those sick had eaten at the premises on Saturday and Sunday.
About 80 people are understood to have been affected, but final numbers had yet to be calculated.
A Metro South health spokesman said tests were still being carried out and it was too early to confirm what caused the outbreak.
“As of Wednesday afternoon, we’d received nine formal complaints, but they relate to multiple people,” he said.
“Metro South Public Health is investigating, with samples and statements taken from a number of people.”
In a statement, a Logan City Council spokeswoman said they were working with Queensland Health to investigate.
“We have taken steps under the Food Act 2006 to ensure there is no further risk until the outcome of the investigation is known,” she said.
“We also encourage people would like to report any other alleged cases of illness to contact Queensland Health.”
However dozens of angry comments were left on an automatically-generated Facebook page for Chin Chin.
“Went here with three friends on Saturday, one of us has been admitted to hospital for food poisoning (around 30 people there from Saturday night alone!). And I’ve been writhing in pain for the last two days,” wrote Benjamin Gunning.
“Absolute disgrace,” wrote Joshua Curtus.
“My partner and I ate there on [Saturday] and we have been in bed sick for 3 days. This place needs a serious clean up… I will never eat there again.”
Julie Holmes and her daughter Tayla are recovering after falling ill over the weekend. They were at the restaurant to celebrate Julie’s birthday.
Eight of the 15 people at Julie Holmes’ birthday dinner on Sunday night fell violently ill.
A sign on the restaurant’s door yesterday read: “Closed for maintenance until further notice.”
Authorities say the closure order does not necessarily mean the restaurant is to blame for the outbreak because it may have been supplied with contaminated food.
Bullshit. Sourcing food from safe sources is part of a restaurant’s responsibility, along with the usual — and limited — cooking, cleaning, chilling and separating.