The sight of a naked woman straddling the top of a house in London caused confusion in the British capital’s East End last weekend.

The incident, which took place on the roof of Toynbee Studios, turned out to be a piece of performance art by Poppy Jackson, part of the SPILL Festival of Performance.

Jackson’s performance piece, entitled Site, attracted a lot of attention from pedestrians and nearby residents. Many took to social media to express their amazement, incredulity, and bewilderment at the event.

The Guardian’s Lyn Gardner described Jackson’s four hour performance as “unassumingly beautiful and quietly moving to behold.” She praised how “Jackson seems to become as one with the building, part of its very architecture, as if her body is an extension of the brickwork.”

However, Britain’s notoriously outspoken tabloids were somewhat less understanding. “Isn’t that a bit chilly?” the Daily Mail’s headline quipped. Meanwhile, a witness told the Evening Standard: “I don’t know how she got away with it. If I was walking around naked I’d be arrested.”

“The piece investigates questions relating to temporality, the body in site, representation, and gender through consideration of the use of the body in performance as an activist practice,” a press release distributed by Toynbee Studios clarified. Jackson later gave an interview responding to public criticism of her performance.

“The work interrogates the boundaries, access points and interaction between ‘interior’ and ‘exterior’ categories. Physical action dually presents the female body within a process of claiming space, whilst attempting to exist as deterritorialized space,” the statement continued.

You can watch a video of the performance here:

Jackson, a graduate of London’s prestigious Goldsmiths art school, previously attracted attention for asking women to donate menstrual blood for a project, and for shaving all of her body hair with a straight razor.

Nude performance art has gained popularity in recent years. Swiss artist Milo Moiré’s controversial “naked selfie” series landed her in jail in July, while Norwegian video artist Hilde Krohn Huse spent three-and-a-half hours suspended naked and upside down by her ankle after a performance went horribly wrong this summer.