OAKLAND (CBS SF) – A man who flew from Oakland International Airport to Houston earlier this year faces a $9,000 fine in an incident where he allegedly refused to wear a mask during the flight, federal officials said.

According to the Federal Aviation Administration, the man was on a Southwest Airlines flight on February 21 when he was asked by a flight attendant to pull up his mask because it did not cover his nose. Officials said he refused. The flight attendant then gave the man another mask, but he threw it on the ground and said he would not wear it.

After the flight attendant explained the mask requirement, the passenger again said he would not comply, saying mask wearing would not be enforced in Texas. At the time, Texas was under a mask mandate, which was not lifted by the state’s governor until early March.

Officials said the cabin crew alerted the captain, who then arranged for law enforcement to meet the plane once it arrived in Houston.

The passenger’s identity has not been revealed.

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The FAA also announced fines ranging from $10,000 to $15,000 to four passengers on other flights for alleged noncompliance with the mask mandate. Officials said passengers assaulted flight attendants in two of the incidents.

“The enforcement actions announced today are part of the FAA’s zero-tolerance policy for unruly and dangerous behavior by passengers,” the agency said in a statement. Passengers have 30 days to respond.

Since January 1, the FAA said they received 2,500 reports of unruly behavior by passengers, including about 1,900 reports of passengers defying the mask mandate.

Masks will continue to be required at airports, on planes and public transit through at least September 13, according to the Transportation Security Administration.