One Direction are mourning the death of their beloved "brother" Liam Payne, who passed away suddenly in Buenos Aires, Argentina, on Wednesday (October 16).

The band shared a heartbreaking message to Instagram on Thursday (October 17), citing "devastation" and memories with Liam that they'll treasure forever.

"We are completely devastated by the news of Liam's passing. In time, and when everyone is able to, there will be more to say. But for now, we will take some time to grieve and process the loss of our brother who we loved dearly. The memories we shared with him will be forever treasured."

The "Gotta Be You" hitmakers continued:

"For now, our thoughts are with his family, his friends, and the fans who loved him alongside us. We will miss him terribly. We love you Liam."

The sentimental message was signed "Louis, Zayn, Niall, and Harry." So far, Louis Tomlinson and Zayn Malik have been the only former One Direction bandmates to share public tributes to their dear friend.

Payne was found dead at the CasaSur Palermo Hotel after falling from a third-story balcony, resulting in fatal injuries including a fractured skull and internal and external hemorrhages.

The "Strip That Down" star was just 31 years old at the time of his tragic passing and is remembered by his 7-year-old son, Bear, sisters Nicola and Ruth, parents Geoff and Karen, friends, former 1D bandmates, and directioners across the globe.

Rest in peace, Payno.

Elvis Duran