A Polish nun who risked her life by hiding Jews from the Nazis during the Second World War has died aged aged 110, the archdiocese of Krakow in Poland has announced.

Sister Cecylia Roszak, who was believed to have been the oldest nun in the world, died last week in the Dominican convent in the city of Krakow, southern Poland, where she had lived for nearly 90 years.

The archdiocese posted a photo of the nun on Twitter with the message: “In Krakow the oldest sister in the word died – sister Cecilia Maria Roszak from the monastery of Dominican sisters.”

Ms Roszak was born on 25 March 1908 in the village of Kiełczewo in west Poland and joined the Dominican monastery of Gródek in Krakow, aged 21.

In 1938, with a group of nuns, she went to Vilnius in Lithuania to establish a new monastery, but the plans were scrapped when war broke out.

During the fighting, the sisters reportedly hid around a dozen Jews from Nazis. One of those she helped was activist and writer Abba Kovner, who later testified at the trial of Nazi war criminal Adolf Eichmann.

German authorities arrested Ms Roszak’s superior and closed down the convent in 1943.

Following the war, Israel awarded the nuns the “Righteous Among the Nations” medal, which it gave to non-Jewish people who risked their lives during the war to save Jews.

After the war Ms Roszak returned to Krakow, where she worked as an organist and cantor for more than 80 years.