President Dr. Lazarus McCarthy Chakwera and the First Lady, Madam Monica Chakwera, have mourned the death of Namibian president Hage Geingob.

Geingob, 82, died Sunday while receiving medical treatment at a local hospital, his office announced.

The Namibian presidency said Geingob’s medical team at Lady Pohamba Hospital did its best to help him, but he died with his wife, Monica Geingos, and children by his side.

In his condolence message soon after the announcement of Geingob’s passing, President Chakwera said he was saddened by the death of a leader he described as a ‘brother and colleague’.

“On behalf of the First Lady of the Republic of Malawi, Madam Monica Chakwera, the people of Malawi, and indeed on my own behalf, I would like to send our deepest condolences to Madam Monica Geingos, the First Lady of Namibia, the bereaved family, and all the people of Namibia on the passing of my dear brother and colleague, President Hage Geingog of the Republic of Namibia,” said the Malawi leader in a statement released a few minutes after the announcement of Geingob’s passing.

Chakwera said Geingob’s leadership and dedication to Namibia and Africa were admirable throughout the continent.

Namibian president Hage Geingob has died at the age of 82

He expressed that hope and prayer that Namibians will use ‘this challenging time to reflect on their personal and collective commitment to the development of Namibia and the liberation of the African people as the late President purposed to do throughout his life’.

“May his legacy endure. Our thoughts are with you during this difficult time,” thus Chakwera concluded his condolence message.

According to ABC News, Geingob was undergoing treatment for cancer. The 82-year-old had a colonoscopy and a gastroscopy on Jan. 8, followed by a biopsy, his office said last month.

He returned home on January 31 from the United States where he had undergone a trial two-day “novel treatment for cancerous cells,” according to his office.

In 2014, he said he had survived prostate cancer. Geingob, president of the southern African nation since 2015, was set to finish his second and final term in office this year.

He was the country’s third president since it gained independence in 1990, following more than a century of German and then apartheid South African rule.

After spending nearly three decades in exile in neighboring Botswana and the U.S. as an anti-apartheid activist, Geingob returned to Namibia as its first prime minister from 1990 to 2002. He also served in the same capacity from 2008 to 2012.

Soft-spoken but firm on advancing Africa’s agenda as an important stakeholder in world affairs, Geingob maintained close relations with the U.S. and other Western countries.

Meanwhile, Angolo Mbumba, Namibia’s acting president, has called for calm, saying in the same post that the “Cabinet will convene with immediate effect in order to make the necessary state arrangements in this regard.”

According to Namibia’s constitution, there should be an election to choose a new president within 90 days of Geingob’s death.