ANCHORAGE, Alaska — A COVID-19 outbreak at a high school wrestling tournament held in April is linked to more than 20 infections in five communities across southeast Alaska, according to health officials.

Ketchikan High School hosted the regional wrestling tournament, an annual event that this year attracted athletes from seven different schools, Anchorage Daily News reported.

Officials from the regional school activities association issued a warning to the school last week on accusations of failing to test competitors and enforce mask orders at the event, as is required by the region’s mitigation policies.

By Thursday, at least 11 students, two staff members and five other residents in the surrounding community tested positive for COVID-19 as part of the school outbreak. Contact tracing showed that at least five people who attended the wrestling tournament were infected with the virus at the time, according to Kacie Paxton, spokesperson for the Ketchikan Emergency Operations Center.

Another five cases associated with the outbreak were found in four other communities that participated in the tournament, bringing the total number of infections that could be traced back to Ketchikan High School to 23.

More cases were reported in Ketchikan on Thursday, but health officials are still determining if they are connected to the tournament, Paxton said.

Ketchikan had a total of 53 active COVID-19 cases as of Thursday.

District officials said that the matter was still under investigation. The Ketchikan Gateway Borough School District, which has 30 days to respond to the warning from the regional school activities association, is looking into exactly what happened and plans to provide information soon due to the high level of public interest, said Katie Parrott, acting superintendent.