In respect of the physical assault, call the police.
You have given notice, tell the council/landlord/landowner that there are people on the land who are trespassers keeping horses which you have not given consent for and you are not responsible for them.
If you did give consent, then you need to give the requisite notice and you can’t say what I have said above.
If they have put chains and padlocks on, I don’t know whether that’s problematical for you or not but if you don’t particularly need to open the gate, what you can also do is put your own chain and padlock on which prevents them entering and if they cut it off, then it’s criminal damage and you can complain to the police and ask them to be prosecuted. Take photographs of the chain and padlock in place.
Because there is animal welfare here you can make an emergency application to court for an injunction to compel these reprobates to remove the locks and allow access and you can ask the court to award costs against them. You could have an injunction probably by the end of tomorrow if you got the application into court first thing.
What may or may not be relevant is why these people come to be on the property in the first place and whether they pay any rent under the terms of an agreement which they seem not to have done.
I would start by getting a solicitor to make an application for an emergency injunction, as soon as you can.
Can I clarify anything else for you?
I am happy to answer any specific points arising from this.
Please take a moment to look at the top right-hand corner of the page and rate my service by clicking one of the stars at the top of the screen.
You may need to login again to use the rating service. Although it says "rate to finish" it doesn't close the thread and we can still exchange emails.
It's important that you use the rating service because that gives me credit.
It doesn't just give me a pat on the head! It's what gets me paid!!
There is also an experts incentive scheme whereby the more 5 star ratings I get I do actually get a pat on the head!
All you need to do is press Submit.
If you still need any points clarifying, I will still reply because the thread does not close.