A New Zealand woman has had her business website "hijacked" by an apparent Islamic extremist hacker group, which replaced her site with photographs including ones depicting Isis flags.

Sonia Crystella noticed the site takeover on Friday night and is concerned not only for the potential loss of data and security, but her own personal safety too -- after spotting a man taking photographs of her from his car.

Ms Crystella, 59, originally from Auckland but who now lives on the Gold Coast, runs a health and well-being website, is an author, designer and public speaker.

When users clicked on to her website -- soniacrystella.com -- over the weekend they were met with images of battle, Isis flags, and men with covered faces, and a message which said the site had been "hacked by Security Crewz".


The message continues, asking "citizens of the world" to "open your eyes wider for what [is] happening around us".

"Humanity is gone in our life now ... It's full of cruelty and suppression ... Killing others is an unacceptable act and this should be stopped ... There is no religion or law [that] permits this action."

In large letters, coloured red, white and green, it ends: "Freedom will rise very soon."

A ticker running under the main message hails Allah in a prayer from the Koran, which ends: "To you your religion, and to me mine."

Ms Crystella said when she first noticed the hack, there was a timer on the page, which she worried could be linked to videos of Isis beheadings.

She spent the weekend trying to find someone to help fix the problem -- first her web domain host in Wellington, Domainz, but it was closed for the weekend, then its Australian branch, Melbourne IT, Wellington police, the Australian Federal Police, and the Australian police terrorism hotline.

Police told her the site needed to be "shut down immediately", because it posed a security risk, and quizzed her for 45 minutes asking "thorough" and "specific" questions, she said -- about her background, her work, anyone who might target her, and a head veil she designed a number of years ago.

They also told her they were aware of five similar incidents in the past few months.

"I've been getting some funny contacts through LinkedIn lately and some strange emails," she said.

"When I went out today [Sunday] I had some guys beside me in a car taking photos of me. It was really scary and I was too scared to look at them."

She managed to note down the car's registration, she said.

Ms Crystella said she was frustrated by the lack of response from Domainz, and was considering legal action against it.

"It's been up for three days that I know of, it's still not taken down, so it just really frightens me -- if it can happen to me it can happen to anyone.

"I'm really surprised they don't have an emergency number, because it could have been one of the biggest companies in New Zealand and everything could have been taken, bank accounts emptied ...

"They've hijacked my website and I haven't got it back and nothing's been done about it, and it's upsetting. My whole website's gone, it's destroyed ... and it's just frustrating because I can't get anything done about it."

She was lucky she did not carry out e-commerce on her website, she said, or the hackers could have had access to customer's bank details.

However, Ms Crystella is in the dark about why she was targeted or the meaning behind the message.

"I don't even know their motives, they haven't contacted me."

Ms Crystella's website was back up and running today after she contacted Domainz this morning.

The company told her there had been a total of 181 attempts in one month to break into her site, she said -- something that had prompted her to think about taking the site down altogether.

"They said I'm not the only one to have this happen to. They said it's worldwide and there are attempts to get into websites continually.

"Even with security measures it's not safe."

She had been advised to change her security systems and passwords every three weeks, at least.

The experience had left her shaken and scared, Ms Crystella said.

It is understood at least one other New Zealand website had hijacked in the same way as Ms Crystella's site and that Domainz has yet to fix it.

The Herald is seeking comment from Domainz.

In the past Security Crewz has been linked to both the hacker group Anonymous and Islamic extremists, while others said the group was simply highlighting flaws in business websites.

Last June a number of Australian websites were targeted by the group, with one report claiming thousands were hacked by Security Crewz in one day. Australia's biggest car mechanic group, Ultratune, was hacked in May last year by the same group, in a hijacking which appeared to be making a statement about the conflict in the Middle East.

The imagery and writing from screengrabs of the hacking message bears stark similarities to Ms Crystella's site.