The grandson is 11 (according to the BBC) and ran out of the house to get help. Thank goodness he got out
Beeb article also says that the dogs were destroyed at the scene. If they could not be safely approached (really quite likely) then yes they would be shot.
The puppies may well have to be euthanised, because it is no longer legal to rehome them, and as they've been living with an utter shit of an owner who was unconcerned they were fighting, it's possible they will never be reliable to be kept as pets. I mean, puppies do fight - it's part of being a puppy - but it's usually good natured play-fighting. Not the sort of thing you have to try to separate with a broom FFS
It's a horrible event, and shows just how shitty some owners are. And it does seem the shits are over-represented in ownership of this breed (and other "status" dogs). No word yet, but I'd be amazed if any of these dogs were properly exempted, muzzle trained, or even trained at all