Police officers found Sinéad O’Connor unresponsive in a London flat on Wednesday just weeks after she had moved to the city, it has emerged.

The Metropolitan police said in a statement on Thursday that officers were called at 11.18am on Wednesday to reports of an “unresponsive woman” at a residential address in the Herne Hill area of south London.

“Officers attended. A 56-year-old woman was pronounced dead at the scene. Next of kin have been notified. The death is not being treated as suspicious. A file will be prepared for the coroner.”

O’Connor’s family broke the news of the Irish singer’s death in a brief statement on Wednesday evening, prompting mourning and tributes from artists and others around the world.

In a Twitter video post shared on 9 July O’Connor filmed herself at a flat, saying she had moved to London and intended to record new songs.

“I’ll make a video because some of you are saying you don’t believe it’s my account; it is my account. But fret not, I’m going to be a good girl,” she said. “I look like shit either way, which is why I didn’t want to make a video.”

Referring to the death of her 17-year-old son, Shane, who died 18 months ago after leaving a hospital while on suicide watch, she said: “But you know the way your kid, unfortunately, passes away, it isn’t good for one’s body or soul to be fair. But anyways, let’s not dwell on that.”

The camera panned around the living room and kitchen, showing a vase with sunflowers and a guitar, which O’Connor said she intended to use to compose songs. The Dubliner had lived in London intermittently over the decades.

Tributes continued to flow. “What Ireland has lost at such a relatively young age is one of our greatest and most gifted composers, songwriters and performers of recent decades, one who had a unique talent and extraordinary connection with her audience, all of whom held such love and warmth for her,” said the Irish president, Michael D Higgins. “May her spirit find the peace she sought in so many different ways.”

In a social media post, the singer Morrissey accused some celebrities of appreciating O’Connor only after her death. “You praise her now ONLY because it is too late. You hadn’t the guts to support her when she was alive and she was looking for you.”