Mourning the loss of life that was, by all accounts so far, preventable.

Editorial

The Instagram post conveyed the pain: “MISSING! Please any information on my brother and Michaela. Please god let these 2 be ok and let us know please”

And with it, a photo of a handsome young couple dressed for a special night, him with a boutonniere in his lapel, her with a wrist corsage.

The anguish, terror and fear is not limited to the family of this pair. Thirty are confirmed dead and officials expect to find more victims in what may be the deadliest structure fire in Oakland history.

Mayor Libby Schaaf promises “a very thorough and methodical investigation so we can discern what in fact happened.”

From what we know so far, this was a disaster waiting to happen. The two-story, 9,880-squarefoot building housed dozens of people in an artist’s collective ominously named “Ghost Ship.”

But it was permitted as a warehouse, not as a residence. And not as a party venue, which is what it had been turned into Friday night. The Facebook page for the “Golden Donna 100% Silk 2016 West Coast Tour” suggests hundreds planned to attend.

There’s a reason governments require permits for residences and entertainment establishments. It’s so infernos like this don’t happen.

The accounts so far suggest this was a fire marshal’s worst nightmare. No sprinklers or fire alarms. Only two known exits. A makeshift stairwell built out of wood pallets.

One man who lived there described a building littered with electrical wires that sometimes sparked. Oakland fire Chief Teresa Deloach Reed said firefighters found the space filled end to end with furniture.

It’s easy to understand how the building went up in smoke and flames so quickly about 11:30 p.m. Friday and why it took firefighters four hours to control the blaze.

It’s hard to understand how this could happen. Oakland City Councilman Noel Gallo had received numerous complaints about parties at the building and illegal dumping on the property. What happened to those complaints?

Inspectors last month had supposedly launched an investigation of garbage piling up on the adjoining lot. That turned into a probe of an illegal interior building structure.

When inspectors returned on Nov. 17, they couldn’t get inside. That was 15 days before the fire broke out. What happened since then? Did the inspectors return? Gallo says they apparently didn’t try.

And what of those who walked into this death trap on Friday night? Many were young, in their 20s and 30s. Did they not sense danger in this makeshift party venue?

So many questions. We await the findings of the mayor’s promised investigation. And we mourn for the tragic loss of life that was, by all accounts so far, preventable.

The accounts so far suggest this was a fire marshal’s worst nightmare.