JUNEAU, Alaska (AP) — Five people who traveled together on a state ferry in southeast Alaska have tested positive for COVID-19, a system spokesperson said Friday.

The individuals boarded the ferry Matanuska in Kake Monday morning, with the vessel arriving in Juneau late that night after passing through Sitka, according to a release from the state transportation department. The state health department believes the individuals were “likely infectious” while on the ship, the release states, and the ferry system is notifying the public “out of an abundance of caution.”

Officials are recommending recent travelers on the Matanuska get tested if any symptoms arise; wear masks in public; and maintain physical distance from non-household members.

Ferry system spokesperson Sam Dapcevich said the Alaska Marine Highway System has a policy of only allowing passengers to get off at their ports of destination. He said the five individuals with confirmed cases of COVID-19 were considered close contacts “only with each other.”

He said the epidemiological investigation of the case continues.

The ship arrived Friday morning in Bellingham, Washington, and crew members will be tested, according to the system release.