The US government's HealthCare.gov website collapsed twice today from a surge of people trying to access the site hours before a midnight deadline to sign up for health insurance.

The site's performance on the final day of a six-month enrollment period was delayed until 8am EDT (11pm EST) after a government tech team noticed a software bug and extended an overnight maintenance schedule to deal with the problem.
A few hours later, new users logging on to the federal website were suddenly unable to create accounts and begin the enrolment process as volume reached what administration officials called record levels. By early afternoon, officials reported the issue resolved.
"Record traffic continues before the midnight ET deadline. As of 2pm, HealthCare.gov had more than 1.6 million visits. As of 4pm, there were more than 840,000 calls to the call center," a US Department of Health and Human Services spokesperson said.
She said the day's high volumes triggered the system's virtual waiting room, a holding page where people can wait to be let into the website.
The system's data services hub, which connects HealthCare.gov to federal agencies, remained fully operational, allowing people already in the system to complete their enrolment, she said.
The delays occurred as healthcare reform faced a crucial test to see how many people sign up for new insurance under the Obamacare marketplaces.
Americans have until midnight on Monday to obtain health insurance under US President Obama's Patient Protection and Affordable Care Act or face fines. The administration has softened the deadline to accommodate those who attempt to apply for coverage by Monday night but run into technology issues.
The administration said the website "has handled record consumer demand well. Over the weekend, the site saw 2 million visits," the government said, and more than 8.7 million visits during the past week.
More than 6 million people had signed up for private health coverage through the new Obamacare insurance markets by last week, surpassing a target set after a disastrous October rollout called the enrolment process into question.
"We admittedly had just a terrible start because the website wasn't working, and despite losing effectively two months, we are going to be reasonably close to that original projection," Obama said said on CBS Evening News.
A successful enrolment would give an important political boost to the administration and its Democratic allies, who are locked in an election year battle with Republicans over the future of Obamacare.
"No one expected us to come back from the brink," White House spokesman Jay Carney said. "But we have."