More than two dozen students from the University of Texas at Austin tested positive for COVID-19 following a spring break trip to Mexico, university and Austin public health officials confirmed.

A group of about 70 young adults traveled together on a chartered plane to Cabo San Lucas in mid-March and since their return, 28 students have tested positive for the coronavirus.   

“Dozens more are under public health investigation,” the Austin Public Health Department said in a statement.  

City officials said that at least four of the confirmed patients showed no symptoms and that they have launched an investigation into the entire cluster.

UT Austin confirmed that while the 28 who have tested so far are students at the school,  they could not confirm if the entire group was made up of students.

“The incident is a reminder of the vital importance of taking seriously the warnings of public health authorities on the risks of becoming infected with COVID-19 and spreading it to others,” said UT spokesman J.B. Bird.

This latest incident comes on the brink of intense criticism travelers are facing for continuing vacation plans despite the pandemic. Florida Gov. Ron DeSantis was recently criticized for refusing to close the state’s beaches, which has been a popular destination for spring breakers.