In a rare publicity move, the Chinese military on Thursday morning published pictures of its intercontinental ballistic missile launch that took place on Wednesday.

The People's Liberation Army Rocket Force published four pictures showing a big, green-painted missile soaring up into the sky after lifting off from a launch vehicle among what appeared to be tropical shrubs.

It was an unusual move for the PLA, which has seldom published photos of its intercontinental ballistic missiles, let alone images of a launch of one.

The military announced on Wednesday that the missile, carrying dummy warheads, was launched into open waters in the Pacific Ocean. It did not specify the missile's type, nor where it was launched from.

According to information published previously by the Chinese military, the PLA Rocket Force now has various types of intercontinental ballistic missiles, including the DF-31AG, the DF-5B and the DF-41.

The newly published pictures have excluded the possibility of the launched missile being from the DF-5 series, because those types are fired from either large, fixed launch towers or missile silos. The missile shown in the pictures had features that resembled those on the DF-31AG, which was declassified and debuted in July 2017 at a parade marking the 90th anniversary of the PLA's founding.

Senior Colonel Zhang Xiaogang, a spokesman for the Defense Ministry, said at a news conference on Thursday that the test was part of the PLA Rocket Force's annual training plan and was intended to examine the weapon's capability and performance, as well as to test the soldiers' operational skills.

When responding to a question about whether the missile test indicates a shift in China's nuclear weapon policy, Zhang said, "China's nuclear policy has a high degree of stability, continuity and predictability. We always adhere to our policy of 'no first use' of nuclear weapons, firmly stick to our nuclear strategy that is defensive in nature, and refrain from arms races. We have made a clear commitment not to use or threaten to use nuclear weapons against nations and areas without nuclear weapons, and have maintained our own nuclear forces at the lowest level required by national security needs."

Shao Yongling, a retired professor of military strategy at the PLA Rocket Force Command College, said the fact that the Chinese military published news and pictures soon after the missile test represents an increased level of openness and transparency.

"Another implication is that the PLA must have wished to use this intercontinental missile test to show the world that China's nuclear deterrence power is real and reliable, given that the country has been facing complex challenges to its national security," she said.