HATTERAS, N.C. (AP) — Ferry service along the North Carolina coast is experiencing interruptions because of a rising number of COVID-19 cases in crew members and mechanical issues on the vessels themselves.

The Virginian-Pilot reports the Cedar Island, Swan Quarter and Hatteras routes are affected, the N.C. Department of Transportation said in a news release. Last Thursday, three ferries on the Pamlico Sound routes and one on the Hatteras route were out of service due to mechanical issues.

In addition, COVID-19 cases are on the rise locally and have impacted recent departure schedules on the Hatteras route. The news release said that while nearly all recent cases have recovered and returned to work, future cases can’t be predicted and could lead to other interruptions.

Bad weather and sand build-up created major delays on the Hatteras-Ocracoke ferry operation during the past few months. The Ocracoke Express passenger-only ferry began operations for the season this week and should ease some of the long waits for visitors heading to and from Ocracoke Island, the department said.