The Guernsey Border Agency was notified of the alleged self-isolation breach on Saturday, a spokesperson for the GBA has confirmed.
The Border Agency said there are “no concerns” of a wider risk to public health as a result of the alleged breach.
“Working with the Sark Authorities and Public Health, the travellers were made aware of the requirement to self-isolate and taken back to their vessel which was escorted to Guernsey where all are now self-isolating.
“Whilst the GBA is investigating this potential breach the Medical Officer of Health in Sark, having reviewed the situation, has confirmed there are no concerns of a risk to public health as a result of this incident.”