The chairman of a German company whose cranes are reportedly being used for public hangings in Iran lashed out at critics and dismissed calls for his company to end its relationship with Tehran on humanitarian grounds.

German construction company Atlas has come under fire from advocacy groups for purportedly supplying cranes to Iran, which then uses them to publicly hang opposition leaders and others.

Iran is a world leader in executions, killing 529 citizens last year mostly by hanging. Another 40 people were hanged over two weeks in January, and about two Iranians are being executed a day under President Hassan Rouhani.

The name Atlas can be seen on the cranes in several photographs of Iran's public hanging ceremonies, in which a masked executioner strings up a man as locals gather to watch, often with their children.

The photographs prompted the advocacy group United Against Nuclear Iran (UANI) to write Atlas Chairman Fil Filipov to demand that his company "immediately terminate all business activities in Iran."

Atlas, which appears to be represented in Iran by an affiliate named Hydro Atlas, says it is not doing business with Iran and does not know how its equipment made its way to the country.

"We do not ship any cranes to this country!" Filipov told the Washington Free Beacon via email when asked about the pictures showing its cranes being used in hangings.

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