A church in New Zealand has been fined after it installed an illegal phone jamming device inside its property to stop phone calls interrupting its religious services. The Economic Development Ministry launched an investigation following concerns from Vodafone that its network was being affected in the area.

"We haven't had any backlash. They have accepted they were responsible for what is an offence and appear to have accepted the fine." the ministry's radio spectrum compliance manager, Chris Brennan sold The Dominion Post newspaper.

The church is understood to have been donated the jamming equipment. It has been illegal to sell jamming devices since August 2009, but not to import them from overseas sellers.

As is increasingly common in many countries, local prisons are typically the only authorised users of active cellphone jammers.

Blocking signals by use of passive systems, such as special coatings on the walls of buildings to prevent signals entering is not illegal, but has the downside of not being easy to "switch off", and block all radio devices from working. The more sophisticated active jamming devices which block phones from connecting to the networks can now be configured to permit authorised phones to make calls.