List of missing New Zealanders falling

The number of New Zealanders missing and unaccounted for remains "fluid" but is gradually reducing, 16 days on from the Asian tsunami disaster.

The Ministry of Foreign Affairs and Trade says privacy issues prevent it from naming the four people for whom the gravest concerns are held, though family members of two of them - Andrew and Belinda Welch - have placed death notices in newspapers and will hold memorial services this week.

The family of another man, Stephen Bond, also presume he is dead.

Yesterday the number of people the ministry had "identified as warranting a concentrated effort to determine their whereabouts" rose from eight to nine.

Spokeswoman Emma Reilly said this was a person who had previously been in the group of people who "may have been in the region" but the level of concern about his or her whereabouts had been upgraded.

At the weekend there were 607 people in that category but by last night that was down to 569.

"So there is still a wee bit of movement, obviously the numbers are coming down but there are names that are going up and down as the level of concern changes."

Two New Zealanders remain in hospital in Thailand.

The Red Cross Call Centre, which is staffed by volunteers, is open from 8am to 5pm daily to take calls and to hear from anyone whose family members have turned up independently.

The information is then passed to the 10 ministry staff who are trying to trace the missing people.