More than 1,500 book bans have been instituted in US school districts in the last nine months, a study has found, part of a rightwing censorship effort described as “unparalleled in its intensity”.

PEN America, a non-profit organization that works to protect freedom of expression in the US, scrutinized efforts to ban certain books from school libraries for its “Banned in the USA” report. The organization found that 1,145 books were targeted by rightwing politicians and activists, including the work of the Nobel prize laureate Toni Morrison.