The Auckland Airport said at 9.13am local time (7.13am AEDT) authorities had cleared the runway to open and for flights to resume.

Police officers earlier responded to “a threat’’ — understood to be a bomb scare. They had been at a spot on Geoffrey Roberts Rd, where the airport is located, since about 8am, the New Zealand Herald reports.

Prior to that, Auckland Airport said all flights had been suspended by police.

The airport later confirmed all domestic and international flights had resumed.

Police had suspended all flights to “ensure the safety and security of everyone on Auckland Airport’s precinct”.

“Police are currently investigating at incident at Geoffrey Roberts Road and specialist groups are on site. Some buildings have been evacuated,” the airport said.

“A section of Laurence Stevens Drive inbound off Puhinui Road is closed by Hape Drive and Geoffrey Roberts Road is currently closed while police are at the scene.

“We ask that all workers and members of the public avoid the area until further notice.”

A Defence Force spokesperson confirmed a bomb squad was at the scene.

“The New Zealand Defence Force can confirm that the NZDF Explosive Ordnance Disposal team has responded to a request for assistance from New Zealand Police at Auckland airport. No further details will be released.”

A police statement earlier said specialist groups were on site and conducting inquiries.

Members of the public heading to the domestic terminal were being told to use Tom Pearce Drive, an alternative road, instead.

“Significant delays are expected,’’ police said.

Parts of Laurence Stevens Drive and Geoffrey Roberts Rd are closed as police work at the scene. Motorists are also being warned to expect delays.

“Police appreciate motorists co-operation ahead of time as we conduct those inquiries at the location,” police said.

Mayank Batra, an operations controller at Swissport Executive Aviation across the road, said the Air New Zealand Airport Campus was being evacuated.

His colleagues were not being allowed down Geoffrey Roberts Rd. Police were telling them there was a bomb threat in the campus carpark.

Mr Batra said he could see six to seven police cars and a fire truck. His building was also being evacuated.

This article originally appeared on the New Zealand Herald and was reproduced with permission