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Delta Air Lines wants to create a national “no fly” list of banned passengers to prevent unruly behaviour onboard aircraft.

The carrier has pushed other US airlines to share their lists of passengers who have been banned during the pandemic for disruptive behaviour, according to a memo to flight attendants on Wednesday, first reported by Reuters.

“We’ve also asked other airlines to share their ‘no fly’ list to further protect airline employees across the industry,” Delta said in the memo. “A list of banned customers doesn’t work as well if that customer can fly with another airline.”

Delta has put more than 1,600 people on its own no-fly list since the COVID-19 pandemic began, the airline said in the memo.

United Airlines has temporarily banned more than 1,000 people since the pandemic began, CEO Scott Kirby told CNBC in March.

The rate of unruly airline passenger incidents had dropped sharply since the start of the year, but remained twice as high as it was at the end of 2020, the Federal Aviation Administration (FAA) said Thursday.

The FAA recorded 4,385 unruly passenger incidents between January and September 2021, according to the agency’s website. More than 3,000 of those reports were related to passengers refusing to wear a mask, it says. It has initiated nearly 800 investigations — far more than any other year since 1995, it says.

The FAA announced in August it had proposed more than $1 million in fines for unruly passengers in 2021.

Flight attendants have told Insider that the rise in passenger violence has left them fearing for their safety. Crew members have reported being spat on, punched, and called racial slurs by passengers.

At a hearing on Thursday, US lawmakers and aviation unions pushed for new action to prevent unruly passenger incidents.

During the hearing, House Transportation Chairman Peter DeFazio asked if there were legal impediments to airlines sharing “no fly” lists. He said the FAA could potentially create a list.

Rep. Eddie Bernice Johnson, a Democrat, asked why the Justice Department was not doing more to prosecute unruly air passengers.

Sara Nelson, president of the Association of Flight Attendants-CWA (AFA) said that the Department of Justice (DOJ) “has been slow to conduct criminal investigations or seek indictments.” Congress should encourage the DOJ to take action, she said.

A Justice Department spokesman said that interference with flight crew members was a federal offense that can result in a maximum penalty of 20 years in prison.