Gardaí are investigating what they say was a "credible threat" to the Intel plant in Leixlip in Co Kildare earlier today.
Hundreds of workers were evacuated while specialist units carried out a sweep of the campus following a suspected bomb threat at around 6am.
Workers en route to the site were instructed to check in with their line managers and those arriving around the time of the alert were advised to park their cars outside the facility.
The buildings were declared safe just after 8.30am and workers were allowed back into the plant shortly afterwards.
In a statement this lunchtime, a spokesperson says normal activity has now resumed at the campus.
Intel has also thanked the Gardaí for their support and the general public for their patience while the matter was being dealt with.