IPOH, May 6 — Flights at the Sultan Azlan Shah Airport resumed yesterday following an almost 24-hour closure which disrupted travel for hundreds of passengers.

It resumed operations about 4pm, with the first flight from Singapore landing an hour later.

The airport was forced to close at 6.40pm on Thursday after a depression was found on the runway measuring 12cm in diameter and a metre-deep.

State Public Transportation Committee chairman Datuk Dr Mah Hang Soon said the cavity was discovered at about 6pm during a routine check.

"Repair works were conducted and it was completed at 12.30am,” he said, adding this was the second sinkhole incident at the airport runway since 2014.

Speaking to reporters at the airport yesterday, Dr Mah said initial investigations revealed that the cause of the sinkhole was due to soil erosion.

"Ipoh has been experiencing heavy rain of late and water had seeped underground causing soil erosion,” he said.

"But a detailed investigation is ongoing to determine the actual cause of the incident,” he added.

Dr Mah said the location of the sinkhole was 780m from the one that occurred three years ago.

Four international and two domestic flights were affected by the closure.

"More than 840 passengers were affected,” he said.

One of the affected passenger, who identified himself as Goh, said he and his wife were supposed to be in Johor Baru for a relative’s wedding.

"The personnel manning the counter claimed they had sent an SMS to inform me that my 12.40pm flight had been delayed to 8.40pm, but I told them I did not receive any message,” he said.

"The airport should have called the affected passengers to inform them of the delay as we had to pay for our transport to get to the airport,” he added.

Another passenger, Lai Yoon Ming, 37, a technician said he had his 9.40am flight to Singapore rescheduled to 3.40pm.

"I will just wait at the airport. There is no point going back home as it will incur additional cost,” he said.

Chef Carmen Ng, 26, who is also scheduled for the 9.40am flight to Singapore, said it was fortunate that she did not have work today.

Ng, who was back in Ipoh to recuperate from a road accident, said she was supposed to meet up with her employer in Singapore during the weekend.

"I have not called him yet. I guess he won’t mind as I am still on leave,” she said.