A Swedish man who tried to build a nuclear reactor in his kitchen says he started the experiment "just for fun".

Richard Handl, 31, from Aengelholm municipality in south-western Sweden, was detained by police two weeks ago and says he started the project as a hobby.

"I have always been interested in nuclear physics and particle physics," he said.

In May, he launched an English-language blog, Richard's Reactor, in which he charted his progress in the project, complete with pictures.

His plan was "to build a working nuclear reactor. Not to gain electricity, just for fun and to see if it's possible to split atoms at home."

Just to make sure everything was above board, he sent an email to Sweden's Radiation Safety Authority.

"Hi! I'm really interested in nuclear physics and radiation," he wrote.

"As a hobby, I have ... gathered the basic materials (and) planned a project to build a very primitive nuclear reactor. You can see my plans here," he added, complete with a link to his blog.

"I'm now wondering if I am breaking a law with this?" he asked in the email.

At that point, his experiment came to an abrupt end.

Two days later "the police and the radiation safety authority came to my apartment," Mr Handl said.

Police questioned him for about half an hour, before releasing him, he said.

Mr Handl's blog can be found at http://richardsreactor.blogspot.com.

AFP