Thousands of people strip naked for photoshoot in Hull for Spencer Tunick art installation

More than 3,200 people from around the world gathered in Hull city centre, stripped naked and painted themselves blue in the name of art. The installation had been arranged to celebrate the city's relationship with the sea by American photographer Spencer Tunick, who is famous for his installations featuring crowds of nude people.

"There's something about the body and how it's juxtaposed with public space – the natural, soft vulnerable body that's up against the concrete world – it creates a dynamic that interests me."

Tthousands gathered at dawn and were painted with four shades of blue body paint in celebration of Hull's maritime heritage. They then posed for a series of site specific installations around some of the city's best known historic locations, including the former Queens Dock, now a city centre park, the Guildhall and the award-winning Scale Lane swing bridge over the River Hull.

This was the largest event of its kind in the UK, and involved participants from 20 countries. Roads in the city centre were closed between midnight and 10am for the photoshoot.

New York-based Tunick has created more than 90 similar human installations worldwide, including at the Sydney Opera House, the Place des Arts in Montreal, Mexico City and Munich, Germany. The artist chooses to shoot the nude form because "clothing is somebody else's art work," he said. "Fashion is art. By taking away the option of fashion I am working with the true essence of equality and nature," said.

"There's something about the body and how it's juxtaposed with public space – the natural, soft vulnerable body that's up against the concrete world – it creates a dynamic that interests me."

He also said that there are many ways to see this installation, and that the blue masses could also represent the rising sea levels caused by climate change. "It's the idea that the bodies and humanity is flooding the streets," he said. His work in the UK has used places such as Gateshead and Folkestone as backdrops.

Stephane Janssen, an 80-year old participant from America, who has posed for him on 20 previous occasions, told the Guardian: "I always say that it's the least sexual thing that I've ever seen in my life," he said. "We are naked, but it is not important. We are equal. Big people, small people, all colours, all walks of life."

The project had been commissioned by the city's Ferens Art Gallery. Tunick's photographs from Saturday will be exhibited in the refurbished gallery in 2017, when Hull will become the UK city of culture, and will be purchased for the Ferens' permanent collection.

Curator of art for Ferens Art Gallery Kirsten Simister said: "When we announced this back in March we were excited but we had no idea how many people here would respond.

"It took off like a rocket from day one with an overwhelming number of people signing up and we are delighted to see how Spencer has brought them together today to create some remarkable new images and unforgettable memories for themselves."