A list of BNP members' details was leaked
Thirty-nine people with addresses in Northern Ireland are on the list of British National Party members leaked on the internet.
The BNP has said the personal details of about 10,000 of its members have been posted on the internet.
Two people in the Republic of Ireland were also on the list.
Regional organiser Kieran Dinsmore said NI members were being advised to "take reasonable steps" to increase their personal security.
"We've had death threats from various republican elements in the country (in the past)," he said.
"We are concerned about our details being put out over the web."
One of the members whose details were leaked was a serving soldier in Northern Ireland.
The soldier is a member of the Black Watch regiment, whose address is given as Palace Barracks in Holywood.
The regiment was garrisoned at the barracks until the early part of this year.
Another BNP member whose details were leaked was Sandy Baxter, a former police officer who lives in Portstewart.
"I'm in a party I firmly believe in and why should I not hold my head high like anyone else," he said.