A nationwide search for a missing 13-year-old Czech boy exposed a bizarre case of identity theft in which a 33-year-old woman spent four months posing as a schoolboy in Norway, police said.

Barbora Skrlova had been hiding from Czech authorities to avoid giving testimony in a 2007 child abuse case, Czech police said.

She was deported back to the Czech Republic and detained after months of fooling teachers, childcare workers and police in Norway by passing herself off as a boy named "Adam", Czech police spokeswoman Andrea Prochazkova said.