(Portland, OR) -- Employees at two Portland Starbucks stores held a daylong strike yesterday after they claimed they suffered retaliation by management for their efforts to organize a union. The employees said the walkouts at the two stores -- located at Grand and Lloyd and at Jantzen Beach -- would last 24 hours. A supervisor at the Jantzen Beach store said her hours were cut from 40 hours a week to 18 after she filed paperwork with the National Labor Relations Board last month. A Starbucks spokesperson says claims of anti-union activity are false. The strikes yesterday came a day after employees at four other Portland Starbucks stores voted to unionize.