Frost appeared to cover the peak of Fansipan mountain in Sa Pa tourist resort of northern Lao Cai province on Dec. 21 morning following the outdoor temperature dropping to below zero degrees Celsius.

The natural phenomenon has been largely caused by the extreme cold spell that has spread throughout northern and northern-central regions over recent days.

At a height of 2,800 metres above sea level, the peak of Fansipan mountain, the highest in Indochina, is widely regarded as the coldest place in the north during wintertime, with temperatures often plummeting to below zero degrees Celsius, thereby causing frost to occur.

The frost typically becomes thicker higher up the mountain.

This is the third time this winter Fansipan Mt. peak has been covered in frost and light snow.

The northern province of Lao Cai is anticipated to endure a severe cold spell in the buildup to the Lunar New Year festival, known as Tet in Vietnam.

The temperature on Hoang Lien Son Mt. range is forecast to drop even lower on the night of December 21.

The peak of Fansipan mountain is left covered in a thick layer of frost.