A doctor who dedicated nearly 40 years to saving others has died after contracting coronavirus.
Dr Alfa Saadu, 68, died on Tuesday afternoon at the Whittington Hospital in north London.
The doctor had been a medical director at the Princess Alexandra Hospital in Essex and Ealing NHS Trust and worked at many hospitals in the capital.
Tributes have been paid to Dr Saadu, including from the former president of the Nigerian Senate.
Two weeks ago Dr Saadu started to show symptoms of coronavirus and immediately self-isolated.
His son Dani Saadu said the family suggested he should go to hospital, but his father insisted he "did not want to take up a hospital bed because others would need it".
Mr Saadu added: "He was a very passionate man, who cared about saving people.
"As soon as you spoke to him about medicine or what was happening with the NHS his eyes would light up - he was very passionate.
"He was working part-time as a locum as he just could not fully retire. He just loved medicine so much.
"He worked for the NHS for nearly 40 years in different hospitals across London and he loved to lecture people in the world of medicine, he did so in the UK and Africa."
'This virus kills'
Despite retiring in 2017, Dr Saadu continued to work part-time at the Queen Victoria Memorial Hospital in Welwyn, Hertfordshire.
During his career he also worked as medical director of the Ealing Hospital NHS Trust and was appointed interim medical director when the trust merged to become the London North West University NHS Trust in 2014.
The Princess Alexandra Hospital, where Dr Saadu worked as a medical director until he left in December 2017, also paid tribute: "Our condolences to you and your family. Our thoughts are with you all."
Mr Saadu warned people to take the government's advice seriously as the numbers of confirmed coronavirus cases and deaths continued to rise across the UK.
"I remember a few weeks ago when Boris Johnson said 'be prepared to lose loved ones'," he said.
"I got really angry and remember thinking, 'why is he saying this? It is not the kind of thing you say on TV'.
"Now I understand what he means. People need to take this virus seriously. I have seen it first-hand - this virus kills people."
Dr Charles Cayley who worked with Dr Saadu at London North West University NHS Trust, described his colleague as a "pleasure to work with".
"His appointment as medical director at Ealing was a landmark moment in improving the number of ethnic minority staff appointed to senior positions in the NHS. We will miss him greatly."
Dr Saadu is the fourth NHS professional to die from coronavirus in a week after the deaths of Dr Habib Zaidi in Southend, Dr Adil El Tayar in west London and Dr Amged El-Hawrani in Leicester.
Former Nigerian Senate president Dr Abubakar Bukola Saraki posted his condolences on Twitter.
Dr Saraki said Dr Saadu had been a chairman of the Kwara State Association, a community leader and traditional office holder as Galadima of Pategi.
Inalilahi Wa Ina Ilaehi rajiun. My condolences go to the family of late Dr. Alfa Sa'adu, the people of Pategi and Kwara State on the death of the foremost medical practitioner who passed away in London this morning.— Dr. Abubakar Bukola Saraki (@bukolasaraki) March 31, 2020