Niall Horan looked somber as he stepped out in London on Thursday in his first sighting since his former One Direction co-star Liam Payne's death.

The 31-year-old Irish singer-songwriter was photographed walking his dog alongside his girlfriend, Amelia Woolley.

Photos published by Page Six showed Horan dressed casually in a dark green jacket, black joggers, and white sneakers during the outing.

He tried to keep a low profile by pairing his outfit with a cap and dark sunglasses.

Woolley looked effortlessly chic in a gray coat, nude-colored top, loose white pants, and white trainers.

Just hours earlier, authorities in Argentina announced that Payne had tragically died at age 31 on Wednesday.

The pop star fell to his death from the third floor of the hotel where he was staying in Buenos Aires, the CasaSur Palermo.

Horan is believed to be the last 1D member to have seen the "Strip That Down" singer before the tragedy.

Payne reunited with Horan on Oct. 2 at the latter's concert in Buenos Aires and later shared a photo of them taken backstage.

On Thursday, all four remaining members of One Direction expressed their heartbreak over Payne's passing in a joint statement.

Horan, Harry Styles, Louis Tomlinson, and Zayn Malik said they were "completely devastated" after learning about their ex-bandmate's passing.

They also said they were taking time to grieve the loss of Payne, whom they described as a "brother" they "loved dearly."

"The memories we shared with him will be treasured forever," the statement 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."

Horan's brother Greg Horan joined them in paying tribute to Payne by sharing an emotional post on Instagram.

"To say I'm heartbroken is an understatement," Greg wrote. "You are only one of 4 lads I was happy enough to take my place in Niall's life as a brother."

He offered his condolences to Payne's family, including the late singer's 7-year-old son Bear, whom he shared with ex Cheryl Cole.

Tags
Niall Horan, Liam Payne, One Direction