Iran nuk site explosion

A British newspaper quoted anonymous Israeli officials on Monday confirming that a massive explosion struck an Iranian nuclear facility in Fordo.
The explosion was originally reported at a conservative American website, and went unconfirmed until Monday. One unnamed official said that Israel is still uncertain "what happened and how significant it is."
Iran has denied the report, but the original online article claimed that a former intelligence official claimed the explosion was real and had "destroyed much of the installation and trapped about 240 personnel deep underground."
The description of the explosion described it as occurring "deep within" the facility, which would be consistent with several scenarios, including an accident. It could also indicate sabotage, but makes an air strike unlikely.
Israel has made no formal statement on the incident, and the quoted officials did not outright deny possible Israeli involvement. Their comments do imply, however, that this was not the case.