Fierce battles ensued.
4 adult outsiders, plus a fledgeling challenged the local family of 4.
Aerial battles abounded. Dive bombing, clicking of beaks, talons directed at the enemy.
Four sorties were made by the interlopers over a period of 3 hours.
High in the sky, 400 metres? Clicking beaks were very audible, loud screeching, birds flying hither and thither.
Whilst daddy stayed on the ground looking after fledge, the females were relentless in the defence of their home turf.
After each battle, they visited me for refreshments. Topping up theie energy reserves. Much adrenaline was coursing through their bodies. Very vociferous whilst scoffing down the food.
Off up into the lookout trees, awaiting the next sortie by the “Bad Gang”
Four times they saw off the wannabe marauders. Calm has returned to the neighbourhood
At this time of the year you are in danger of getting swooped in some streets 
My “Magpie Family” leaves me alone as they know sustenance is available. 
A man walked through the park with his dog on a lead, the dog was crapped on.
A lady walked through the park last evening and was swooped until she was out of the park.
The turf war is continuing. The interlopers are relentless. Every day, be it daybreak or dusk, and all hours in between.
My group have been putting up a tremendous fight. Though it is starting to take its toll.
The male has an injured wing and can no longer fly.
I think a relative came to lend some muscle yesterday.
The interlopers zeroed in on the earth-bound male and attacked him viciously. The females came to his rescue and put paid to those blighters, fighting them off.
This morning I have not spotted the male. Neither have I seen the youngest of the fledgelings. Over the weekend, the rain was relentless. All the magpies were sodden, though they still battled with those scoundrels.
Saturday evening, I was keeping an eye on the youngest fledgeling, and it was so waterlogged that it was unable to fly up onto a safe tree branch and might have spent the night on the ground. Sunday, the rain was heavier, for longer, once again, the fledgeling was sodden and unable to fly up into the tree.
I watched my two females pin a outsider male to the ground and relentlessly attack him. Beaking him, pinning him to the ground, he was crying out in distress and it looked like my ladies were going to finish him off. Somehow, he broke away and flew up into the sky with the ladies in hot pursuit.
The battles are ongoing. With very short breaks between each sortie.
These turf wars can go on for up to six weeks, even longer. This one has been raging for about two and a half weeks.
We had a big one years ago,left two dead.
Thankfully there seems to be an invisible line across the garden these days which no one crosses.
I have not seen the flightless male so far today. It has been daylight for 8 hours now.
Went looking for the youngest fledgeling, found a bunch of grey, downy feathers in the park. Something made a meal of it. It was the weather that done him in. Two days of relentless rain saw it sodden and unable to lift itself off the ground into the safety of a tree.
What bad luck 
Sadly, I think my gang of magpies are going to lose this turf war.
An hour ago, one of the females returned with a badly injured right leg. Noticeably skewwhiff at the knee joint.
Can only hop on one leg.
Down to one fit fighter now. Against 4 or 5 aggressive fighters.
Not holding out much hope. Still have not seen the flightless male at all today.
We have seven magpies living in a big tree at the bottom of the garden, they yell at me when the water bowl needs filling. One in particular likes a bath every day during the warm weather, They are fierce like yours and sometimes attack the other smaller birds who come for food. I get quite annoyed at them for it as there’s plenty for everyone. They’re not frightened of me they just keep out of my way if I’m busy outside. They hated my Dageus when he was alive as Dageus would chase them out of HIS garden.
Final shake-out of the turf wars.
Starting grid
My group - 1 male 2 females and 2 fledgelings
Interlopers - 4 - 5 mixed adults
The war went on for 3 weeks with multiple fierce battles daily.
My male was injured (damaged wing) early on and took on the duties of looking after the fledgelings.
The females fought valiantly, with one sustaining a leg injury, which healed in about 4 - 5 days.
One fledgeling disappeared, might have been old enough to flee the protection of the group.
I came across the youngest fledgeling’s scattered feathers last Monday morning (26th Oct) after a weekend of very heavy rain.
As a direct result of the fledgeling being waterlogged and unable to lift off the ground into the safety of the trees,
an unspecified predator made a meal of the little-un.
3 days later I came across the body of the grounded male, sans head. Maybe a Powerful Owl was the predator in this case.
They often cleanly decapitate their prey to consume the brain—which is incredibly rich in fats and protein—leaving the heavier, less nutritious body on the ground.
The other option would be the introduced European Red Fox.
Foxes are notorious for surplus killing. If they find a vulnerable bird or clear access to an area, they will instinctively bite the head off and leave the rest of the carcass completely intact.
My gang now consists of 1 male, most likely from the other group, one original female and one fledgeling.
The male is dominant at the moment. Stealing food off the female. He has a tight reign over the fledgeling.
I have witnessed at least half a dozen times the fledgling dropping its body low to the ground, trembling its wings, and gaping its beak open while making high-pitched calling sounds when the male is close by. This shows an act of “appeasement” to show they pose no threat to the male.
One time I watched the male flap one wing and the fledgeling immediately dropped to the ground, that is, he was standing, then he was sitting on the ground. I looks amusing but I am sure the fledgeling was not laughing.
I never once witnessed this appeasement when the original male was in charge.
Turf wars are over. It must be said, the interlopers came out victorious.
I am left with a reduced “family” which I will continue to look after as if there were no turf wars.
That sounds so sad poor things, but nature can be so cruel at times. đź«Ş
I wonder why it happened, the incoming group must have had their own home so why the take over.
This stuff happens all the time in nature.
The new group have a need to expand their territory. Built in second nature.
They do not always win. If they lose, then they go back to their original territory with their tails between their legs.
The way of nature.