MELBOURNE - A former prime minister of the Cook Islands, Joseph Williams, has died of COVID-19 in Auckland, New Zealand's health ministry said on Saturday, taking the number of coronavirus-related deaths in the country to 24.Williams, who was in his 80s, was a well known doctor as well as a politician and author, living in New Zealand. He was briefly prime minister of the Cook Islands in 1999 after having served as the South Pacific nation's minister of health and education."Dr Williams was seen as a leading figure in the Cook Islands medical community and he will be sadly missed," New Zealand's director-general of health, Ashley Bloomfield, said in a statement.New Zealand's largest city, Auckland, has been under restrictions to fight the spread of the coronavirus since an outbreak last month. Prime Minister Jacinda Ardern on Friday extended the 2.5 alert level until at least mid-September after the country reported the COVID-19 death of a man in his 50s."Today's sad news again reinforces the importance of our shared vigilance against COVID-19, the very serious consequences the virus can carry with it," Bloomfield said.