ZURICH (Reuters) - Switzerland has asked state-controlled Swisscom for day-old mobile phone data to help judge whether measures to restrict people's movements and slow the coronavirus's spread were working, a federal health ministry official said on Thursday.

"We wanted to know if these measures were influencing people's mobility," Daniel Koch, head of infectious diseases at the federal health agency, said at a press conference in Bern, seeking to address concerns that the government was intruding into the private sphere.

Koch said the Swisscom data was 24 hours old and provided a retrospective picture of people's movements, adding "it had nothing to do with current data or surveillance, it was really about seeing if there were patterns in people's movements and was only focused on public spaces."

(Reporting by John Miller, editing by John Revill)