Chernobyl's last wedding: The couple who married as a nuclear disaster unfolded

It was just after midnight. Iryna Stetsenko had finished doing her nails for her wedding, opened the balcony door and was battling her nerves to get to sleep.

In a nearby apartment packed with guests, her fiancé Serhiy Lobanov was asleep on a mattress in the kitchen.

Then a "rumble" disturbed the quiet, says Iryna. "It was as if a lot of planes were flying overhead, everything was humming and the glass in the windows shook."

Serhiy says he "felt a shake, as if some kind of wave passed", wondered if it was a mild earthquake, and fell back to sleep.

The 19-year-old trainee teacher and power plant engineer, who was 25, were looking forward to married life in the newly built Soviet city of Pripyat. They had no idea that the world's worst ever nuclear accident was unfolding less than 2.5 miles (4km) away.

Reactor number four at the Chernobyl power plant – in what is now northern Ukraine - had exploded, spewing out radioactive material that would spread across swathes of Europe.

Forty years later, the highly radioactive remains of the plant are in a warzone. The couple now live in Berlin, having uprooted their lives a second time - this time to escape conflict, not a nuclear disaster.

But on the morning of 26 April 1986, Serhiy remembers waking around 6am, full of excitement, to find his wedding day had dawned gloriously sunny.

He had errands to do - bed linen to take to a friend's apartment where he and Iryna planned to sleep that night, and flowers to buy.

He says he saw soldiers in gas masks outside, and men washing the street with a foamy solution. Some men he knew from his work at the nuclear plant told him they had been called in urgently because "something happened", but they did not know what.

As he looked out from the friend's high-rise apartment, he spotted smoke rising from reactor four.

It would later become clear that firefighters and power plant workers had spent the night risking lethal doses of radiation to tackle a huge toxic blaze.

"I felt a bit anxious," he says. Drawing on his training, he took some fabric, wet it and put it across the apartment entrance as a precaution to catch radioactive dust, he adds.

He then rushed to the market. Unusually for a Saturday morning, it was deserted, so he picked five tulips for the bouquet.

Iryna, who was staying with her mother in the family's apartment, says the phone kept ringing overnight. Her mother sounded "alarmed", she says, by neighbours calling to say "something terrible" had happened. But there was little detail.

Information was strictly controlled in the Soviet Union. They turned on the radio, but there was no mention of any incident.

In the morning, her mother rang the authorities: "They told her not to panic, all planned events in the city should go ahead."

Officially, everything carried on as usual. Children were sent to school.

Viewers in the UK can watch What Happened at Chernobyl at 20:30 on Monday 20 April on BBC One, and on iPlayer from 0600.

The Last Dance........

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