Hackers infiltrated Apple supplier Foxconn's computer network, exposing employee e-mails and passwords as part of worldwide protests against working conditions at the Taiwanese company's factories.

On Thursday protesters in the U.S. joined others around the world and handed a 250,000-signature petition to employees at Apple's Grand Central Station store in New York.

Speaking to AFP, Sarah Ryan from protest organizer Change.org said: Our goal is to create a dialogue with Apple.

We want to work with them to improve their working conditions.

The protests come after the New York Times published an influential article last month detailing harsh working conditions at Foxconn factories.

The article exposed labor in harsh conditions and excessive overtime in the Chinese factories where workers assemble millions of iPads and iPhones.

In response, Apple chief executive Tim Cook wrote an email to staff saying the company was inspecting more factories and opening up its supply chain for independent evaluations by the Fair Labor Association.

Published by 9to5mac.com, Cook wrote: Every year we inspect more factories, raising the bar for our partners and going deeper into the supply chain.

We've made a great deal of progress and improved conditions for hundreds of thousands of workers. We know of no one in our industry doing as much as we are, in as many places, touching as many people.