LONDON—Britain reported a surge in cases of the Omicron coronavirus variant on Saturday, which government advisers said could be just the tip of the iceberg, and London’s mayor declared a “major incident” to help the city’s hospitals cope.
The number of Omicron cases recorded across the country hit almost 25,000 as of 6 p.m. on Friday, up by more than 10,000 cases from 24 hours earlier, the UK Health Security Agency (UKHSA) said.
