Rapper Professor Green has joined the fight against 'anti-homeless' benches designed with a metal bar down the middle to prevent vagrants and the homeless lying down or sleeping after they were highlighted in Bournemouth.

Artist Stuart Semple was the first to draw attention to the "repulsive and hostile" benches, posting a photo on Twitter and Facebook, branding them "another gross design against humanity". The photo has since gone viral attracting widespread condemnation. Semple is now planning a global campaign against hostile design which will enable people to "name, shame and stop" architecture which seeks to punish homeless people.

Green, who previously fronted a BBC Three documentary investigating rising youth homelessness, has added his voice to the chorus of outrage. He wrote on Instagram: "Anti Homeless benches in Bournemouth. What's the message here? 'Hey you poor sods with no safety net - you better really hope life doesn't throw any shit at you now! And god forbid you make a bad life decision! Cause you won't have the 'comfort' of this bench to sleep on! Ha!'.

"Again, nothing done to tackle the problem, just something to make it more invisible so we can pretend it isn't happening." More than 37,000 people have liked this post.

Green, whose real name is Stephen Manderson, posted again after seeing a story from local newspaper Bournemouth Echo about Poole Council's plan to fine begging and homeless people from 1 February. He wrote: "This is right doing my nut in. 'Hey man or woman without anything but the clothes on your back, because of the unfortunate situation you find yourself in, we're going to fine you £100, which you don't have, because you don't even have somewhere to sleep, and we're going to move you on from where you're sleeping currently'.

"So then what happens? The homeless are criminalised. This is getting ridiculous. No solution, just punishment."

Green has since posted another photo, this time of a poster which was put up in reaction to similar benches in Kingston, Canada in 2016. The posters encourage people to "fix" the benches, providing advice on which tools can dismantle the obstructions on the benches.

The flyer reads: "It's recently come to our attention that the City of Kingston has been installing new public benches with a metal divider in the centre. This pesky bar makes it impossible to lie down and get a good night's sleep, let alone cuddle or smooch!

"Clearly some bureaucrat in the Parks Department made a mistake. So we thought we'd save them the embarrassment and repaired a dozen benches. All we needed was a pair of adjustable pliers ("channelocks") and a few wrenches (7/16, 9/16″, or 5/8″, depending on the bench)."

Bournemouth Borough Council explained that a small number of benches were recently adapted in the town centre after "numerous complaints" from members of the public and traders. A spokesperson said: "The complaints related to a number of the benches being unavailable to members of the public throughout the day due to people lying on them during the daytime."

The outrage was not universal, as some understood this explanation. Alan Flash Coleman commented on Semple's Facebook post: "It's not the night sleepers the problem it's the ones that lay in all day spewing their mess everywhere and make it impossible for people with mobility problems like myself to sit and rest."

The council spokesperson added that the council runs a "wide range" of services for homeless people but that they needed to strike a balance. The council stated: "As a Council, we need to maintain a careful balance between our responsibility to the wider public to ensure that amenities are available to them, and our duty of care to vulnerable members of our community, including people rough sleeping."

Homeless charity Crisis has criticised the strategy as "short-sighted". Paul Noblet said: "There are far more humane ways to solve rough sleeping than putting up barriers. This short-sighted response will only add to the stigma surrounding homelessness at a time when we need communities to pull together and tackle this growing problem."

The charity released research in December 2016 which found 60% of the homeless people surveyed had experienced an increase in defensive architecture like spikes or segregated benches. More than a third of those surveyed reported they were unable to find anywhere to sleep or rest as a result.