Definitely. Similar seedlings of this species are common in the region - people should stop planting it.

There were so many, we dug them all out but I stuck one in a pot to see if it would grow so we could identify it. Apparently, it will not so this photo is of the dying plant! So, the stalk of the plant isn't red, but green with red fuzz. The stalks of the young leaves are red though. I had a look over the neighbours fence and don't see anything similar but there is a thriving climber so it might be hidden. Thank you for your help.

I don't know why Rina, I just cannot get that spelling in my head. I almost went for the 'y' but knew I didn't know! Thx for the fix. You're welcome Kieran. You may wish to check up on what mixes they like (I'm unsure) but I'd move it out of the peaty mix & into something more fast draining.

The blue colored grass is blue fescue, Festuca ovina glauca. The chartreuse next to it is some sort of low growing juniper, possibly Juniperus horizontalis 'Lime Glow". The taller, dark green conifers appear to be slender Hinoki cypress, Chamaecyparis obtusa 'Gracilis'. Can't see anything clearly enough or in enough detail in the first photo to identify anything else.