Iran are still struggling to keep Bieber and Kim at bay
Iran's censors are struggling to keep Justin Bieber's abs off Instagram.
The tattooed pop star's pouty, shirtless poses have recently reappeared on Iranian smartphones, along with lingerie shots of Kim Kardashian and red carpet photos of Jennifer Lopez.
Mahmood Enayat of the London-based research group Small Media said a colleague in Iran confirmed he was able to access the racy images.
"I am sure he has enjoyed it," Enayat said.
Bieber's was one of at least 983 accounts previously blocked in the Islamic republic, according to a paper being presented at a technology conference in Berlin. One of the paper's authors, security researcher Frederic Jacobs, said Kardashian's and Lopez's pages were also blocked.
A smattering of fashion pages - Burberry, Gucci and Jimmy Choo - were subject to the same restrictions, as was the odd political account - a page devoted to Iranian reformist politician Mohammad Khatami, for example.
The recent collapse of those blocks is awkward because Instagram is one of the few social networking sites easily accessible to Iranians and had been held up as a showcase for what politicians there describe as "smart filtering", or targeted censorship.
The administration of President Hassan Rouhani touts the technique as a way to ease Iran's blanket bans on popular foreign sites while reassuring hardliners that objectionable content will remain out of reach.
The re-emergence of Lopez's flesh-baring dragon dress and Kardashian's sexy selfies suggests it isn't going to be that easy.
"It does seem a little bit embarrassing," said Internet researcher Mahsa Alimardani, who worked with Jacobs on the paper.
Alimardani and Jacobs say the snaps reappeared in Iran after Instagram began encrypting connections between smartphones and the site's servers in the past month.
The encryption means that third parties can't easily tell whose accounts users are connecting to, frustrating censors' attempts to zero in on any particular photographs.
It's not clear if - or how - officials in Tehran will react to the change.