Diaz, 34, had visited Peru's Machu Picchu on Friday carrying a green bag with a red star and the words "Serve the People" in Chinese.
The phrase, a slogan of the late Chinese Communist leader Mao Zedong, touched a nerve among Peruvians still recovering from the Maoist Shining Path insurgency of the 1980s and early 1990s that left nearly 70,000 dead.
"It alludes to a concept that did so much damage to Peru, that brought about so many victims," Peruvian human rights Pablo Rojas told the Associated Press. "I don't think she should have used that bag where the followers of that ideology did so much damage."
"I sincerely apologize to anyone I may have inadvertently offended," Diaz said Sunday in a statement e-mailed to the AP. "The bag was a purchase I made as a tourist in China and I did not realize the potentially hurtful nature of the slogan printed on it."
Karel Navarro / AP
Diaz said in her statement she had been in Peru as part of 4 REAL, a Canadian TV show that celebrates young community leaders around the world, the AP reports. She also praised Peruvians' beauty and warmth and said she hoped "for their continued healing."