To keep unwanted people out of a safe area so that they are unable to escape the consequences of having made their own area fatally unliveable, with the implication being that to let them in would only be to share their fate.
After the French run out of food, we'll hold the door shut in England until it all goes quiet.
To be completely finished off after a series of harrowing events.
Taken from the scene in the movie "Casino" where Nicky first sees his brother beaten to near death with baseball bats and then chucked in a pit. Then he get's beaten to near death and thrown in the same pit. And the last we see of Nicky is as they shovel dirt in on his face and you see him wheezing and puffing the dust out of his mouth with his last breaths.
I'd already left the house late, and there was a demonstration in the town centre so I lost another 20 minutes before I got to the motorway which was slow moving because of heavy rain. Time was tight when I got to the car park but there was a shuttle bus leaving for the terminal and I managed to jump on. Unfortunately it was going to Terminal 4, not Terminal 1, so by the time I went back to the car park, got the right bus and got into the terminal it was 40 minutes before my flight. But they said I was too late and wouldn't let me check in, even though I only had hand luggage. The next flight wasn't until morning. So I had to go home again. And I had to buy a whole new ticket. And pay for the car parking as well. Not to mention extra petrol. I was puffing casino dust the whole way home.