NEW YORK, NY - JUNE 09: Tom Petty performs onstage during the Songwriters Hall Of Fame 47th Annual Induction And Awards at Marriott Marquis Hotel on June 9, 2016 in New York City. (Photo by Larry Busacca/Getty Images for Songwriters Hall Of Fame)

Fans worldwide are in mourning, after the announcement that rock icon Tom Petty died last night, of a heart attack in his home in California.

It came as a shock to many, as Petty had only recently finished his latest tour, a 40th Anniversary celebration with his band The Heartbreakers.

He had hinted that this may be his last circuit, saying “I’d be lying if I didn’t say I was thinking this might be the last big one,” but many believed it to be an empty threat.

Midway through the tour, however, Petty made news for what was seen as a show of support for transgender rights.

In the performance of one of his most famous songs, “American Girl,” Petty regularly projected pictures of a diverse group of women.

On this tour, the video footage included a photo of transgender actress and activist Alexis Arquette.

Arquette came out as transgender in her late 30s, and died last year, aged 47, from complications after having lived for almost 30 years with HIV.

Related: Alexis Arquette’s family release moving statement praising her ‘brave’ fight for trans equality

The photo took on particular significance when Petty played a sold-out show in New York on July 26, just hours after Trump announced his transgender military ban.

Many hailed Petty’s inclusion of Arquette as a strong political statement, considering the timing.

David Arquette, Alexis’ brother, thanked Petty on Instagram for the gesture.

Petty hadn’t been shy about expressing his opinion on other political topics. In an interview with Billboard in 2014, he lashed out at members of the Catholic community.

“I’m fine with whatever religion you want to have, but it can’t tell anybody it’s OK to kill people, and it can’t abuse children systematically for God knows how many years.”

“It seems to me that no one’s got Christ more wrong than the Christians,” he continued.

Related: Sam Smith is paying Tom Petty royalties for ‘Stay With Me’

He also notoriously refused the rights of his songs to a number of Republican political candidates, even going so far as to file a cease-and-desist when George W. Bush tried to use Petty’s song “I Won’t Back Down,” in his Presidential campaign.

In contrast, Petty was glad to let then-President Obama walk onstage to the song at the 2012 Democratic National Convention, saying he “got chills.”