Police in the western Tokyo suburb of Musashino have been fingerprinting and photographing homeless people and gathering other personal data on them on a voluntary basis, police officials said Wednesday.
The officials said they had heard the practice had begun around 1984, but records for this year contain only the fingerprints of three homeless people.
The homeless in Musashino voluntarily gave prints of their left index fingers after being asked by officers from the Metropolitan Police Department's Musashino Police Station, according to the officials.
Police are keeping the fingerprints along with the people's names, birthplaces and places they are sleeping, the officials said.
The deputy chief, Kiyonobu Yuge, said the voluntary fingerprinting was so officers could check a homeless person's identity if necessary at some point in the future.
"We will continue to take their fingerprints if necessary," Yuge said. "Fingerprinting is merely a confirmation seal."
A human rights group has criticized the fingerprinting.