Spanish police said their investigation began in January after a company on the Mediterranean island of Mallorca reported an employee had "become infected but hidden his illness."
Days before an outbreak, the man showed COVID-19 symptoms but refused his colleagues’ suggestions to go home and self-isolate, police said in a statement.
After work, and showing no improvement, he went for a PCR test before visiting a gym and returning to work the next day.
Though his team leaders told him to go home after he allegedly had showed a temperature of more than 104 degrees Fahrenheit, the man refused.
He walked around his workplace, lowering his face mask and coughing on people, saying, "I’m going to infect you all with the coronavirus," according to police.
At the end of the day, his PCR test came back positive.
His colleagues were then tested, with five returning positive results. They in turn infected family members, including three 1-year-old babies, police said.
At the gym the man visited, three people tested positive and also infected family members.
None of those infected required hospitalization, police said.
A judge charged the man and released him on Saturday evening to await trial, Majorca Daily Bulletin reported.
The Associated Press contributed to this report.