The ban on flights in America has been lifted, what is known so far

The ban on flights in America has been lifted after airlines were halted for about four hours.

However, officials say that the effect of this widespread ban on flights may last for several days.

Earlier, due to a problem in the communication system of air traffic control in America, flights were stopped across the country.

The former head of the National Transportation Security Board in the US said that there has never been such a widespread suspension of flights in the US since the September 11, 2001 attacks.

US President Donald Trump told Fox News that it does not appear that the problem was caused by any cyber attack or AI.

Speaking to the BBC's US media partner CBS News, Robert L. “It's shocking that this could happen in this day and age,” Sumwalt said.

US Homeland Security Secretary Markwayne Mullin has said that there is no indication of any attack on America behind this incident and everyone is safe.

Air Canada said all flights between Canada and the United States have been canceled until Friday evening.

Markwayne Mullin repeatedly reassured people that this was not 'another 9/11'.

Earlier, American aviation officials had ordered to stop all flights citing security reasons. He described it as 'extraordinary circumstances'.

At a White House press briefing, Markway Mullin rejected claims that the outage was linked to a Microsoft outage that many people had experienced a day earlier.

Mullin said authorities are working with unprecedented speed to ensure everyone is safe and to help stranded passengers.

He further said that the general public was never in danger. In his words, "There was never any threat to anyone's life."

CBS report said that this problem has occurred in the communication system due to network update.

Multiple sources have told CBS that the technical glitch that led to the nationwide grounding was caused by an update to the private communications network that connects America's air traffic control system.

According to CBS, L3Harris operates this network. After the update the network rebooted and then crashed.

On its website, L3Harris describes itself as a leading provider of communications systems for the world's most advanced airspace, weapon systems and command and control platforms.

L3Harris did not immediately respond to the BBC's request for comment.

Meanwhile, BBC correspondent Simon Atkinson from Australia has said that the country's largest international airport in Sydney has said that all flights related to America have been stopped for the time being.

According to Jack Horton of BBC Verify, the ban on flights in America is being compared to previous incidents.

In a press conference regarding the nationwide ground stop in America, Homeland Security Secretary Markwayne Mullin repeatedly said that this incident is not like 9/11.

BBC Verify spoke to Dr Guy Gratton, Associate Professor of Aviation and Environment at Cranfield University.

"This appears to be the most serious incident since 9/11, but clearly not at that level," he said.

When asked about similar incidents, Dr. Gratton mentioned the incident that took place in America in the year 2023, when flights had to be stopped due to a malfunction in the Notice to Air Missions (NOTAM) system.

He said, "That situation lasted for 1 hour 52 minutes. During this time, about 9,500 flights were delayed and about 1,300 flights had to be cancelled."