The Centre for Health Protection is investigating two food poisoning clusters involving seven people.
The first cluster involves two men and three women, aged 15 to 20, who fell ill after having lunch at a food premises in Yuen Long on July 29.
Four sought medical attention while one required hospitalisation and was later discharged.
The other cluster comprises two men, aged 29, who fell ill after having takeaway lunch from the same premises on July 29.
One sought medical attention but did not require hospitalisation.
All are stable.