MEXICO CITY - A journalist was gunned down this week as he left a holiday party in the Mexican Caribbean resort town of Tulum, human-rights officials and an international media group said yesterday, bringing to 12 the number of reporters killed this year in the country.

Alberto Velazquez, of the newspaper Expresiones de Tulum, was killed on Tuesday.

Velazquez had written articles critical of local officials, and his paper had received threats, according to the Committee to Protect Journalists. In a statement, the group quoted colleagues as saying that Velazquez was shot by a gunman on a motorcycle, and they believed that it was related to his reporting.