SydPath laboratory in Australia said on Monday that 1,000 people received a false negative COVID-19 test ahead of Christmas after previously reporting that only 400 people receiving an incorrect test result.

The laboratory at St. Vincent Hospital in Sydney previously said 400 patients tested on December 23 and 24 received a false negative COVID-19 result but since said 995 people were given incorrect test results on Christmas Day.

"These people had in fact tested positive to COVID-19," SydPath medical director Anthony Dodds previously said about the 400 test results. "As soon as we became aware of this issue this morning, SydPath immediately commenced the process to contact these impacted individuals," The Hill reported.

The laboratory said the false negatives were caused by human error and the testing system was strained because of the large number of tests the lab had to process ahead of the holiday season.

The laboratory said in a statement Monday that the people who received an inaccurate COVID-19 test result can expect to get their new test result by Monday night but "in fact their true result had not yet been determined."

"We are sincerely sorry for this error and acknowledge the significant impact it has had on those involved," the laboratory said. "SydPath have put procedures in place to ensure this cannot happen again," they added.

False Negative COVID-19 Tests Australia
SydPath laboratory in Sydney, Australia, had 1,000 people with a false negative COVID-19 test ahead of Christmas. Above, a man has a swab taken at a drive-through COVID-19 testing clinic at Bondi Beach in Sydney on December 21, 2021.Rick Rycroft/AP Photo

Australia's New South Wales state reported more than 6,000 new COVID-19 cases on Monday and confirmed its first death from the Omicron variant.

The fatal case was identified as a man in his 80s who was infected at an aged care facility in western Sydney. He was fully vaccinated but had underlying health conditions.

New South Wales, the country's most populous state, reported 6,324 new infections Monday, a fall of 70 from the record number a day before. There were 524 people in hospitals, including 55 in intensive care.

New measures came into force in New South Wales on Monday, including limits of one person per 2 square meters (22 square feet) in bars and restaurants and required "check-ins" with QR codes in hospitality venues.

Health Minister Brad Hazzard said the state government is considering lifting the requirement for health workers to isolate after being exposed to COVID-19 because of staff shortages.

Victoria state reported 1,999 new cases on Monday with three deaths.

State COVID-19 response commander Jeroen Weimar said Victoria has moved to random genome testing for the omicron variant to better understand its spread.

The Associated Press contributed to this report.