The Ministry Director of Civil Defence is pleading with people to turn their emergency alerts back on, after an early morning notification caused many to disable the.

The emergency alert system accidentally sent out several loud cell phone notifications to thousands of people during the night.

Alert notifications, including a high-pitch ringtone, were sent between 1:30am and 2am on Wednesday morning. Many alerts were sent multiple times to the same device.

The emergency alerts can be disabled - with many on social media saying they've done just that.

Sarah Stuart-Black, Civil Defense Ministry Director told Newshub they would tell those people to "please turn it back on".

"I understand that it was an error - and I apologise."

A post on Facebook this morning came under fire for saying it only affected a "small number" of users, and it was quickly edited.

"We apologise to those who have been inconvenienced, and will request all testing is carried out during daylight hours in future."