The plume was deflected to the SE, by mild westerly winds. Activity was most vigorous at one crater, but several other craters on the short eruptive fissure were also active with less frequent explosions.
Last image gives a good overview over the eruptive site.
The eruption was slightly less vigorous than on 18th of December. Activity was mostly limited to one crater. Initially the plume was rater light colored, and narrow at its base. Later the ash content of the plume greatly increased, and the plume turned black. This was the second last day of the eruption, it ended on December 28.