Ukrainian President Volodymyr Zelenskiy is expected to visit the Chernobyl exclusion zone on April 26 to commemorate the 35th anniversary of what is considered the worst civilian nuclear disaster in history.

Ahead of the International Chernobyl Disaster Remembrance Day, dozens of people gathered in the ghost town of Prypyat and held an overnight vigil with 35 candles in memory of those who lost their lives in the accident.

An explosion and fire caused by a reactor meltdown at the Chernobyl power plant, located 110 kilometers north of Kyiv on April 26, 1986, sent clouds of lethal nuclear material across much of Europe.

Prypyat, home to some 50,000 people, was evacuated along with other communities in a 30-kilometer exclusion zone around the radioactive wreckage.

Dozens of people, particularly firefighters and other first responders, died as a direct result of the disaster, but radiation poisoning is believed to have killed thousands more across Ukraine, Belarus, Russia, and other countries in the years that followed.

In 2016, a crumbling "sarcophagus" used to contain radiation from the smoldering reactor was replaced with a $2.3 billion metal dome in a bid to stop future leaks. More than 200 tons of uranium remain buried inside.