PROVINCETOWN, MASS. (WHDH) - More than 250 confirmed COVID-19 cases have now been linked to a recent virus outbreak in Provincetown, officials said.

RELATED: Biden health officials discussing mask recommendations as variants drive surge in COVID-19 cases

Surveillance efforts have identified additional cases associated with the cluster that prompted the popular Cape Cod tourist town to issue a public health advisory earlier in the week, according to town manager Alex Morse.

As of July 20, 256 cases were said to be associated with the outbreak, up from the 132 people who tested positive for the virus after people flocked to the town over the Fourth of July weekend.

A total of 190 of the cases are Massachusetts residents, including 109 people who live in Barnstable County, officials said. The other cases are among people who live in other states.

Boston health officials on Tuesday urged recent visitors to Provincetown to self-isolate and get tested for COVID-19

A COVID-19 vaccination and testing center at the Veterans Memorial Community Center will remain functional through Friday, July 30.

In an effort to curb the spread of the virus, Provincetown officials are now advising people to wear masks indoors where social distancing cannot be achieved, regardless of their vaccination status.

On Wednesday, Nantucket joined Provincetown in urging people to wear masks.

All unvaccinated individuals, including children under the age of 12, are required to wear masks both outdoors in crowded areas where social distancing cannot be achieved and in public indoor spaces, per CDC guidelines.

RELATED: 80 fully vaccinated Mass. residents have died from COVID-19 as breakthrough cases surpass 5,000

Masks remain mandatory for all individuals on public and private transportation systems.

People are also being advised to use caution when around large crowds in indoor spaces and to avoid handshaking, kissing, hugging, and other forms of close contact that increase the risk of transmission.

Anyone who feels ill should get tested for the virus and stay home, officials said.

(Copyright (c) 2021 Sunbeam Television. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

Join our Newsletter for the latest news right to your inbox