Liam Payne's One Direction Bandmates, Including Harry Styles, Gather for Emotional Funeral Service Near London

Family, friends and fans of Liam Payne have gathered to pay tribute to the late star.

On Wednesday, Nov. 20, the late singer's girlfriend Kate Cassidy and his former One Direction bandmates Harry Styles, Louis Tomlinson, Zayn Malik and Niall Horan were among those in attendance to memorialize Payne — who died on Oct. 16 at age 31 — in a funeral service held in a 12th century church in the English countryside northwest of London.

The musician's ex, Girls Aloud singer Cheryl, with whom he shared 7-year-old son Bear Grey, was also in attendance, along with Payne's friend James Corden and One Direction co-creator Simon Cowell, who helped launch the band's career on The X Factor back in 2010. Cowell was joined by his fiancé Lauren Silverman.

Payne died after falling multiple stories from a balcony at the CasaSur Palermo Hotel in Buenos Aires, Argentina.

On Nov. 7, a press release by the National Criminal and Correctional Prosecutor's Office No. 14 revealed that the former One Direction member's toxicology results showed traces of "alcohol, cocaine and prescription antidepressants" in his body.

Prosecutors also said in the release that "self-harm of any kind and/or physical intervention by third parties were ruled out" as contributing factors in his death.

A forensic doctor judged Payne's death was caused by "multiple trauma" and "internal and external hemorrhage" as a result of the fall, per the release.

Prosecutors also concluded that the "Strip That Down" singer was "not fully conscious or was experiencing a state of noticeable decrease or loss of consciousness at the time of the fall."

On Oct. 23, Payne's father, Geoff Payne, had traveled to Argentina and was cooperating with authorities for the investigation into his death.

Buenos Aires police found Payne's hotel room “in total disorder” after the singer's death. Minutes before the balcony fall, hotel staff alerted emergency services, reporting in a 911 call that the singer had been “trashing the room,” officials said.

A source close to the late singer's girlfriend Cassidy, 25, who attended the funeral with friend Damian Hurley, told PEOPLE his "erratic behavior started ramping up" when she left their vacation.

"Like you could see from the Snapchat videos, he was a different person around her," the insider told PEOPLE after his death.

After his death, producer Sam Pounds announced the release of Payne's first posthumous song titled "Do No Wrong." However, he then canceled the release out of respect for Payne's family.

"Today I’m deciding to hold 'Do No Wrong' and leave those liberties up to all family members. I want all proceeds go to a charity of their choosing (or however they desire)," he wrote in a post on X (formerly known as Twitter).

Pounds continued, "Even though we all love the song it’s not the time yet. We are all still morning [sic] the passing of Liam and I want the family to morn [sic] in peace and in prayer. We will all wait."

Payne was also set to star on Netflix’s upcoming music competition series Building the Band as a guest judge. After his sudden death, the fate of the show — which also stars Nicole Scherzinger, Kelly Rowland and AJ McLean as host — remains unclear.

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A source told PEOPLE that the series producers were shocked by the news — and he was so fulfilled by the experience he wanted to continue working with bands after production ended.

"Liam seemed so genuinely happy to be on set. He looked healthy, and was smiling in all his fan interactions, signing things and chatting with them between takes," said a PEOPLE staffer who was on set in late August. “He was having a great time doing what he loved, and showed no signs of any underlying issues.”