Updated at the bottom with a statement from Arnold and Maria. First posted at 12:23 p.m.

Arnold Schwarzenegger's 13-year-old son Christopher was injured in a surfing accident in Malibu recently, TMZ reports. Injuries are said to have included “multiple broken bones” and a collapsed lung.

It's not clear if he was riding a hard board or a body board, according to the site.

The boy's 17-year-old brother Patrick tweeted:

Thank you everyone for your messages about my brother. This kid is strongest kid I ever seen. Keep praying.

CNN says the younger bro face planted into something hard in the mishap last weekend. The news org reports that he's expected to fully recover.

That kind of accident is unusual in surfing, especially around here, as most beaches in SoCal are sand-bottom. But Malibu's Surfrider state beach does have a stone bottom. Waves in the region have been minimal, although there was a south swell last week.

So who gets worked in small, warm summer surf? It's rare, though not unheard of.

Amid Arnold and Maria's pending divorce, maybe it was a cry for help.

Update: Arnold and Maria issued this joint statement.

A few days ago our son Christopher suffered an accident at the beach. While it has been a very scary week, Christopher is surrounded by his family and friends. He is a

brave boy and is expected to make a full recovery.

On behalf of our entire family, we want to sincerely thank the paramedics and lifeguards who responded so swiftly as well as the doctors, nurses, emergency room and hospital staff who have cared for our son. They have been extraordinary to him and to us. We thank everyone for their thoughts and prayers and ask for respect and privacy for Christopher and our family.

Thinking about this some more, we've come to the conclusion that sustaining such extreme injuries while using a board, surf or Boogie, isn't unheard of but is quite rare, especially in the relatively small waves around here.

However: Getting hurt like this while body surfing (we used to call it “whomping”) in shallow water is way more common. People have even ended up paralyzed. What happens is you end up diving head first into sand, stones or whatever's at the bottom, with tons of water coming down on you. (Fun if you're 12 or, in Christopher's case, 13). We're going to go out on a limb and assume this is what happened. But “surfing” sounds way cooler.

[More]: Turns out he was riding a Boogie board, according to a recording of the 911 call for help from mama Maria.

[@dennisjromero/djromero@laweekly.com]

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