Seagate's factory in Limavady closed on Thursday
Almost 1,000 people have lost their jobs after Seagate Technologies' factory in Limavady ceased production.
The plant shut its gates for the final time on Thursday after more than 10 years manufacturing components for the electronics industry.
The parts will now be produced in a factory in Malaysia.
The factory's closure date was brought forward by six weeks. However, workers will be paid until the end of October and redundancies are not affected.
Simon McGuinness is one of many Seagate workers who are now unemployed.
"I gave 10 years of my life to that place now and basically they've upped and left us.
"It's not even a matter of we're not doing a good job because we were doing a good job, it's just they can get it cheaper somewhere else.
"It's a bit worrying wondering what the future holds for me and how I'm going to cope with bills," he said.
Plant manager William O'Kane said rising costs forced the factory to close.
"We constantly operated under cost pressures.
"The workforce and the management team took enormous steps over the years and were very diligent and very successful in driving cost out of the operation.
"They did keep the factory successful for 11 years however inevitably that was not enough and the cost pressures from the Far East could not be surmounted via efficiencies at a local level," said Mr O'Kane.
Seagate Technologies' Northern Ireland operation will continue production at its plant on the Buncrana Road in Londonderry.