LONDON (AP) — British Prime Minister Theresa May says that 120 high-rise buildings in 37 parts of Britain have failed fire-safety tests — a 100-percent failure rate.

Authorities are urgently testing buildings' cladding in the wake of the June 14 blaze at London's Grenfell Tower, which killed at least 79 people.

Fire officials say panels affixed to the building's exterior helped the blaze, which began with a refrigerator fire, shoot up the 24-story tower.

The tragedy has prompted hard questions about building regulation and fire safety.

Political leaders are trading accusations about who is to blame. Labour Party leader Jeremy Corbyn said Wednesday that it showed "the terrible consequences of deregulation and cutting corners."

But May said "there is a very wide issue here" that can't be pinned on any single government.