Car Tyre Damaged - What Caused This.

Picked up a flat last night, never seen anything like this before, any ideas. I didn't hit anything and I stopped as soon as I thought there was an issue, tyre deflated very quickly.

I'd say either a deep cut in the tyre that was widened by use and pressure or a defect in the original manufacturing but It looks more like a simply cut/tear.

[Sid Squid]

There's minute cracks all over the pictured area - age. Specifically aged rubber and a physical injury caused by who knows what. Being run at incorrect pressures can contribute to this.
Bear in mind that a tyre doesn't need to be of an advanced age to suffer age related damage, exposure to UV and less than ideal atmospheres accelerates the ageing process quite dramatically, much of this can occur before the tyre is fitted and used.

Funnily enough I checked my tyre pressures 3 hours earlier, one was a couple of psi under but not this one. I never push my tyres, it's a Skoda Octavia 1,9TDi estate and I'm no boy racer. I have fired off an email to the manufacturer with the photo offering them the tyre for examination. It's only been on the rear of the car for about 6 months and done about 10k miles.

[Sir Trev]

That looks a lot older than 6 months to my untrained eye. As Squidly says, there are a lot of tiny cracks, that suggests this may have been quite old stock or incorrectly stored.

[NTECUK]

Should be a date code on the tyre .
go check it out.

Inside view. Date code is wk44 year 11. To correct myself, I think these were fitted Feb 2012 and have done about 25k miles. The fronts where changed 6 months after.

Looks like maybe a bit of metal of some foreign object you ran over made a puncture and it just failed? 25k is pretty good though even for a rear!

[NTECUK]

hum think this needs close examination .
we change only a few tyres .
Never seen a split like that.

[NTECUK]

what make are they.