Volunteer Service Abroad has been the victim of a ransomware attack, however experts say no information was taken.

A spokesperson said the attack happened last Friday and the organisation's computer systems were encrypted.

"VSA was locked out of its servers. We also disconnected all systems on Friday 14 May and began investigations into the access. Staff were able to work again on Monday 17 May using our current operational systems," the spokesperson said.

"Our back up was also encrypted. Our servers held mostly historic information."

The group responsible demanded a ransom, but none was paid.

Instead, VSA "engaged immediately with the Cert NZ, Privacy Commissioner, NZ Police and other government agencies".

The group was different to that responsible for the Waikato District Health Board attack, VSA said.

It believed their main motivation was "getting money from us as an organisation".

VSA chief executive Stephen Goodman said "It has been a stressful time and we have lost important historic data, but our IT infrastructure meant we were able to respond quickly and get back to support our partners in 11 countries in the Pacific region.

"It seems to be too common these days and I just wonder what we could be achieving in the world if the people with these IT skills instead put them to good use rather than criminal activity."