Three prison inmates were found with a total of 19 mobile phones in their stomachs and anuses after a metal detector check.
The group were given X-rays after setting off a metal detector during a check in a prison in the city of Presidente Bernardes, in the south-eastern Brazilian state of Sao Paulo.
One had five small mobile phones in his anus, and another four. The third had ten of the devices in his stomach, along with headphones.
The two with the phones secreted in their anuses did not require treatment but the man with ten in his stomach had to undergo surgery to remove them.
Police seized the devices and the inmates are the subjects of an ongoing investigation.