The world famous Kaikoura 'UFO' sightings of December 1978. They appeared on Wellington air traffic radar and were sighted by hundreds of people.

There is some weird material among the searchable online Central Intelligence Agency trove of declassified archives.

In 1978, strange lights were reported in the sky above Kaikoura.

The sighting, intense public interest and media coverage of the "UFO", as well as interest from the prime minister Robert Muldoon, sparked an official inquiry by the air force.

Reuters The CIA online archive gives the public access to 13 million pages of declassified material.

An air force Orion was sent on a reconnaissance mission to Kaikoura in January 1979, but the official investigation concluded natural phenomena were the most likely explanation.

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TVNZ Strange lights appear in Wellington night sky during 2016's 7.8 magnitude Kaikoura earthquake.

Strange lights have also been reported in the skies in New Zealand - including Kaikoura - before earthquakes, known as earthquake lightning.

The CIA trove cites the Kaikoura incident, which was referred to in a publication called the Journal of Scientific Exploration in 1987.

"The New Zealand UFO sightings of December 31, 1978, are unique among civilian UFO reports because there is a large amount of documentary evidence which includes the recollections of seven witnesses, two tape recordings made during the sightings, the detection of some unusual ground and airplane radar targets, and a 16mm colour movie."

The CIA trove also includes archives of controversial CIA programmes, such as the MKULTRA programme, in which subjects were hypnotised, tested for psychic abilities and given LSD.

In another programme called "STARGATE" the CIA investigated whether psychic powers existed and whether they could be harnessed for military and intelligence purposes.

Documents on "remote viewing" sessions are now online, detailing subjects' efforts to beam their mind towards targets. A remote viewing is defined as the "acquisition and description, by mental means, of information blocked from ordinary perception by distance, shield, or time."

An overview document describes the programme's focus on psychokinesis - the ability to move objects with mental thought - and telepathy, and remote viewing.

STARGATE was declassified in 1995 and the CIA admitted its research did not provide any useful intelligence.

The online database has its own UFO section.

Regarding earthquake lights, or lightning, seismologists aren't in agreement about the causes, but one study documents hundreds of sightings of strange lights, glowing, and aurora-like phenomena from 1600 to the 19th century.

The study in the Seismological Research Letters suggested a charge builds up in rock inside the Earth's crust and, as it becomes rapidly unstable in a quake, expands outward, the electrical charge transfers from below the surface to the surface, or above, depending on the conductivity of the rock, and appears as light.