Malaysian health authorities have raised concerns about a growing number of coronavirus deaths and serious cases involving children, after a surge in overall infections forced the Southeast Asian nation into a strict lockdown.

Prime Minister Muhyiddin Yassin declared a two-week “total lockdown” from June 1 to June 14, as daily Covid-19 cases and deaths hit record numbers, with the government warning the outbreak may be linked to more contagious variants.

Malaysia recorded the deaths of three children aged below five due to the coronavirus in the first five months of this year, the same number recorded over the whole of 2020, according to Health Ministry Director General Noor Hisham Abdullah.

A total of 27 children, including 19 below the age of five, also had to be treated in intensive care between January and May after contracting the virus, up from eight cases last year, Reuters reports.