KAWASAKI--A community center here used by many ethnic Korean residents is on alert after receiving a New Year’s card filled with hateful and threatening messages.

“Wishing you a Happy New Year. Let’s wipe Korean residents in Japan off the face of the earth. If there are remaining survivors, let’s kill them brutally.”

The threatening postcard was delivered by Jan. 4 to Fureaikan, a public facility to promote multicultural exchanges and understanding between Japanese and foreign-born residents, particularly ethnic Koreans.

“Making such threats is an unforgivable act,” Kawasaki Mayor Norihiko Fukuda said at a news conference on Jan. 23.

The city plans to file a damage report with police, accusing the sender, who is unknown, of possible forcible obstruction of business, the mayor said.

Fureaikan is owned by the city and located in the Sakuramoto district of the city’s Kawasaki Ward, where many Korean residents reside. It is managed by Seikyusha, a social welfare organization.

Seikyusha initially planned to file the complaint with police, but Fukuda decided that it would be “appropriate for city authorities to take action instead."

Under police guidance, the center has taken security precautions that include keeping curtains closed even during the daytime so that the inside is not visible from the outside.

Some of the entrances have been closed off. The facility has also assigned extra nighttime staffers.

The city will also dispatch additional security personnel to the facility.

“Employees have been placed in a state of extreme tension,” said Tomohito Miura, secretary-general of Seikyusha.

The facility has a wide range of users, from infants to the elderly.

During the period from Jan. 4 to Jan. 21, 2,315 people visited the center, which was 843, or about 27 percent, less than the number from the same period the previous year.

Citing that the number of visitors had been on a slight increase before the incident, a facility staff was shocked at the drop and said, “This is an abnormal situation.”

“Gaikokujin Jinken-ho Renrakukai,” an organization of scholars and lawyers to protect foreigners’ human rights, issued a statement urging the central government and the Kawasaki city government to take emergency measures in response to the hateful postcard.

The group has also started collecting signatures on the internet from those who support the statement.