Liam Payne’s girlfriend Kate Cassidy shares heartbreaking letter to singer following his tragic death

Liam Payne's girlfriend Kate Cassidy has written an open letter to the One Direction singer on social media a week after his passing.

Payne, 31, died in the Argentinian capital of Buenos Aires last week after falling from the third floor balcony of his city centre hotel, where he'd reportedly stayed to watch former bandmate Niall Horan perform in the days prior.

He'd been staying at the CasaSur hotel with girlfriend Kate Cassidy, who had left to go to her home in Florida in the days prior to the tragic event.

Police originally told press that they'd received an emergency call reporting 'an aggressive man who may have been under the effects of drugs and alcohol'.

Alberto Crescenti - the head of the state emergency medical system - previously said on Argentina's Todo Noticias TV channel that the singer had fallen from his hotel room into a courtyard.

The preliminary autopsy results into the 'Strip That Down' singer's death showed last week that Payne - who shares an eight-year-old son named Bear with ex-girlfriend Cheryl - had died from multiple injuries sustained in his fall, which led to 'internal and external haemorrhaging'.

Cassidy had previously written a statement about her boyfriend's passing on 18 October, and has now penned a heartbreaking letter to the father-of-one.

"I don't even know where to begin," she began, also sharing several snaps of the couple together. "My heart is shattered in ways I can't put into words.

"I wish you could see the huge impact you've had on the world, even as it feels so dark right now. You brought so much happiness and positivity to everyone-millions of fans, your family, friends, and especially me. You are so incredibly loved.

"You are because I can't say were-my best friend, the love of my life, and everyone you touched felt just as special as I did. Your energy was contagious, lighting up every room you walked into."

Cassidy continued: "None of this feels real, and I can't wrap my head around this new reality of not having you here. I'm struggling to figure out how to live in a world without you by my side. Together, we got to be kids again, always finding joy in the smallest things.

"Liam, you had the kindest soul and the most fun-loving spirit. It feels like I've lost the best part of myself. I can't imagine a day without your laughter and love. You brought so much light into my life.

"A few weeks ago, we sat outside on a beautiful evening manifesting our lives together. I keep your note close, even though you told me not to look at it. It said, 'Me and Kate to marry within a year/engaged & together forever 444.'

"Liam, I know we'll be together forever, but not in the way we had planned. You'll always be with me. I've gained a guardian angel.

"I will love you for the rest of my life and beyond, carrying our dreams and memories with me everywhere I go. Forever yours, Katelyn 444."

The sweet post also included an image of a letter seemingly written by Payne, where the words, 'Me and Kate to marry within a year / engaged 2together 4ever' are visible.