U.K. Prime Minister Boris Johnson confirmed Monday that at least one patient infected with the new omicron variant of Covid-19 has died in the country.

“Sadly yes, omicron is producing hospitalizations and sadly at least one patient has been confirmed to have died with omicron,” Johnson told reporters on a visit to a vaccination clinic near Paddington, London, according to Sky News.

“So I think the idea that this is somehow a milder version of the virus, I think that’s something we need to set on one side and just recognize the sheer pace at which it accelerates through the population. So the best thing we can do is all get our boosters.” he said.