In a Facebook post, the department said it was experiencing technical difficulties.

“We apologise for the inconvenience and are doing our best to ensure the system returns to normal,” it said.

Nitizen Monkticon Mike complained that he had been waiting at the department since 8am.

“Can the department provide an estimated turnaround time whenever there are situations like this? We have taken a day’s leave for this, we can’t simply come back all the time,” he said.

Another user, Shankar Segran, questioned why there was no backup system in place.

“You expect people to queue for hours and wait with no hourly update. You have the elderly and children queuing too,” he said.

User Zhen Feng said the department should immediately come up with damage control measures.

“What are your plans to navigate those affected? In the event that it cannot be solved by today, can the appointments be rescheduled within the week? Otherwise, the next available new slots are likely to be a month from now. How many of us are going to burn our air tickets or accommodation due to your system glitch?” he asked.

In a Facebook post later in the day, the immigration department said its system was back in full swing at 1pm.

The public may visit https://www.imi.gov.my for more information.