There is an additional article in the Australian.
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The article is confusing as it states the flight was destined for Melbourne but then goes on to say 'the 737 flight to Adelaide'.
However, it also states the flight diverted to Mildura and made two missed approaches there due to unforecast fog at Mildura followed by a landing. If that is the case, with the caveat that the media has got such things wrong before, then this incident is definitely newsworthy and potentially very serious.