Damaged Starbucks Korea containers are seen at local civic groups' press conference decrying the brand, held Thursday in Gwangju. (Yonhap) A man in his 60s is under investigation for public intimidation, police said Friday, after he posted a threatening message against people using Starbucks products.The man on Wednesday posted that he will "kill anyone carrying around Starbucks coffee," according to the Uijeongbu Police Station. He told police that he did not actually intend to kill anyone when he wrote the post.The incident is part of a widespread boycott of Starbucks Korea, which sparked outrage Monday with its "Tank Day" marketing campaign. May 18 marked the anniversary of the Gwangju Democratic Uprising in 1980, during which hundreds of protesters were killed in a bloody crackdown ordered by Gen. Chun Doo-hwan.Chun had risen to power through a military coup in 1979 and would go on to become president later that year.Starbucks Korea's Tank Day campaign was deemed highly inappropriate because of the historical significance of the May 18 protests and the fact that the military had mobilized tanks and heavy equipment in the crackdown. Despite the brand's official apology, Koreans across the country have called for a boycott of Starbucks.President Lee Jae Myung himself called the marketing campaign "inhumane," saying it negated Korea's sense of community and democratic values.The unionized delivery workers under the Korean Federation of Service Workers' Union on Thursday released a statement saying they will no longer handle deliveries related to Starbucks."With the 'Tank Day' promotional event, Starbucks Korea used the painful memory of the military slaughtering Gwangju citizens with tanks as a mere marketing tool ... This is not just a marketing misstep, but either ignorance or deliberate disregard for history, neither of which can be tolerated," the group said.The hotly-disputed campaign had also used phrases like "Slam on the desk," which was thought to reference another bloody incident linked to Chun.Under the Chun administration in 1987, student activist Park Jong-chul was tortured to death in a police interrogation. The officials in charge then made the infamously outrageous claim to the media, saying that the investigators "merely hit the desk with a slam" which supposedly shocked and killed the 22-year-old Park.