Chulalongkorn University on Tuesday confirmed six more staff had been found infected with Covid-19, raising the total to 13.
The Covid-19 Committee of Chulalongkorn University said it screened 230 people who came into contact with previously infected people at the university's staff accomodation, and six tests returned positive.
This brought the total number of cases to 13. The infected staff were being treated at King Chulalongkorn Memorial Hospital.
The committee said it would test another 389 people who may be at risk. This would raise the total number of tests to 619.
The panel would work closely with other agencies to urgently find the source of the infection.
All confirmed infections were among staff members.
