How pigs were escaping

Recently I had put up some articles about my pigs escaping from my training block. I thought that they had been getting out under the wire around where I feed them as I could get them back into the block through this place. A couple of days ago I had Mike Jones in with his young dogs in for some training and the dogs put I bit to much pressure on the black and white boar and forced him out of the block and down into the hut block. Fog had stayed on the boar so we went down through the pig block with the intention of opening the gate in the gully and trying to get Fog to chase him back into the block. I had not been down to this gate for the last couple of weeks and was very surprised to find the gate wide open. Fog and the black and white boar came back in the gate with out any trouble. It was now that it dawned on me what had actually happened. A couple of weeks ago I arrived home to find that some person had managed to open the padlock on my main road gate and left it open, also the next set of gates up the drive had been left open. I never found out who had done this and I never thought about going up the back gully to check on that gate. So it looks like some mongrel has come in with the intentions of trying to let my pigs out. Lucky for me that my pigs are used to their environment and prefer to stay close to home. If any person knows who the culprit is that has tried to let my pigs out I would like to know.