A South Korean man hurled human feces into the Japanese Embassy in Seoul on Friday to protest Tokyo's sovereignty claim to a pair of islets controlled by South Korea, but he was freed by police despite carrying out an identical attack last August, Yonhap news agency reported.

The 49-year-old dayworker, identified only by his surname Choi, threw a plastic bottle containing his own excrement over the embassy's wall around 8:50 p.m. Friday, the same day Shimane Prefecture held an annual event to assert Japan's long-standing claim to the Takeshima Islands, Yonhap said Saturday.

The agency said police booked Choi and are investigating the incident, but that they chose not to detain him.