Washington, Jan 11 : All flights across the US currently remain grounded after a huge computer outage left the passengers stranded, international media reported.. Passengers have been left waiting on the tarmac after the Federal Aviation Administration (FAA) suffered a nationwide system error, which has left flights grounded indefinitely, Mirror reported. The system, critical for relaying essential information to flights, has been out since Monday evening, and it's now starting to affect services in and out of the US, as per the reports. The FAA notified that the system was down via an Air Traffic Control System Command Center (ATCSCC) advisory, stating that the US NOTAM system failed at 20:28 UTC. It said that technicians were working to restore the system, but that there was no estimated time for the resolution of the problem, media reports said. According to the Air Traffic Control System Command Center: "The NOTAMS outage continues with no current estimate time of restoration. A hotline has been activated." Bettina Inclan, who has been left waiting at Ronald Reagan Washington National Airport, tweeted: "Update from our United pilot - The down system doesn't let him check flight plans and follow federal regulations," Mirror reported. /IANS