Image copyright RCAHMW Image caption The £103m nuclear power station at Trawsfynydd was in operation between 1965 and 1991

An amateur photographer who caused a decommissioned nuclear power station to be put on lockdown has been jailed for six months.

Convicted robber Nicolas Bates, 29, scaled a 6ft-high fence at Trawsfynydd in Snowdonia, which shut down in 1991.

Some 100 staff were put on lockdown by the security breach on 16 March.

Bates pleaded guilty at Caernarfon Magistrates' Court to trespassing on a protected site, possessing knives and cannabis and motoring offences.

District judge Gwyn Jones told him: "Basic commonsense and a very elementary knowledge of physics suggests nuclear sites are dangerous places and there is still a potential risk of harm from radiation."

Bates, of Faseman Avenue, Coventry, was spotted by a contractor who noticed he was not wearing a hard hat or hi-vis clothing in a restricted area, the court heard.

He claimed he carried out research on Wikipedia and was taking photos of what, he thought, was a derelict site.

However, he was found to be in possession of a lock knife, while a hunting knife and smoke grenades were found in his car.

Bates claimed the knives were used to cut wires when entering derelict sites.

Image copyright Getty Images Image caption After decades of exposure to Snowdonia weather, parts of the reactor buildings are decaying structurally and need removing

Sion Hughes, defending, said the lock-knife was for camping and there was no suggestion it had been used to threaten anyone.

A probation officer said Bates was a personal trainer with mental health issues.

Bates was disqualified from driving for nine months and ordered to pay £115 for failing to have car insurance.

The judge ordered he be deprived of the photographs of the site which, if in the wrong hands, "could potentially cause a risk of harm".