Mick Jagger and designer L'Wren Scott pose on the red carpet at the Metropolitan Museum of Art Costume Institute Benefit celebrating the opening of Alexander McQueen: Savage Beauty, in New York in this May 2, 2011 file photo. [Photo/Agencies]

FASHION, MUSIC WORLDS GRIEVE

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Police said a female was found "unconscious and unresponsive" in an apartment building in the upscale Chelsea neighborhood. Fire officials, who responded to a cardiac arrest call, said the woman was dead when they arrived.

Julie Bolcer, of the city's Office of the Chief Medical Examiner, said the office had not received the body nor begun work to determine the manner of death.

"Given the timing, that individual will probably be examined tomorrow and if everything is straightforward, the cause and manner of death would be available by tomorrow," she said.

Foul play was not suspected, police said.

A single bouquet of yellow daffodils was placed in front of the glass-fronted, high-rise building where Scott lived. Police cordoned off its entrance as a swarm of media gathered across the street.

The Rolling Stones were on tour, currently in Perth, Australia. It was not known whether they would cancel their concert there, scheduled for Wednesday.

Musician and fashion friends of the couple took to Twitter to express their grief.

"Devastated to have lost my friend," tweeted rocker Bryan Adams, who has photographed Scott. "Rest in peace my dear I'm gonna miss you. Condolences to all that were close to her."

Jagger's first wife, Bianca, said she was "heartbroken to learn of the loss of the lovely and talented L'Wren Scott. My thoughts and prayers are with her family."

American fashion designer Marc Jacobs said: "You'll forever be missed."

The British Fashion Council described Scott as a woman who inspired many.

"She will leave behind an exceptional legacy however we are so proud to have had her in our midst. At this sad time our thoughts are with her friends and family," it said in a statement.