(Bloomberg) -- Some international schools in Hong Kong were closed Thursday after a Covid-19 outbreak at a gym, where at least nine staff members and clients were found to be infected with the virus.

A 27-year-old trainer from Ursus Fitness in Sai Ying Pun tested positive, Hong Kong’s Centre for Health Protection said Wednesday. His sample was collected on Monday and he last went into work on Tuesday.

Kennedy School, which belongs to the English Schools Foundation group of international schools in Hong Kong, said in an email sent to parents Thursday that it would close its campus due to a positive Covid case connected to the outbreak at the gym.

Two other schools, Kellett School and French International School, also said they closed campuses due to positive Covid-19 cases, but didn’t state whether it was linked to the gym outbreak. Some staff at the French school were asked to come in for coronavirus tests.

Hong Kong schools only resumed in-person teaching last month after about a year of at-home learning. Even now, the majority of schools allow just a limited number of students to attend in person and most classes are still conducted online from home.

Ursus Fitness said on its Facebook page Tuesday that a member of staff had tested positive and that it would be closed until further notice. The following day, it said five staff were in the hospital after testing positive. A client was also confirmed to have the virus, it said. Sai Ying Pun is a neighborhood on Hong Kong Island.

Soho Active, part of the Soho House club in Sheung Wan, also reported a case involving an employee. The trainer taught a private lesson Tuesday morning and tested positive the following day, according to Alice Lam, head of membership and communications.

“All staff members in direct contact with this person have been notified and will remain at home in quarantine for the next 14 days,” Lam wrote in an email. “The member who had direct contact with this person has also been notified accordingly.”

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