In the early hours of 26 April 1986 a reactor exploded at the Chernobyl nuclear power station. The disaster at the Soviet plant remains the worst nuclear accident in history.
An exclusion zone, which has a radius of 30km and covers an area roughly the size of Luxembourg - remains in place around the site in Ukraine. Although largely uninhabited by humans, there are signs that animal life is returning.
This collection of striking photos offers a glimpse inside the exclusion zone.