Los Angeles (CNN) -- Additional police officers were patrolling Los Angeles International Airport and two other airports Wednesday after a former Transportation Security Administration employee was accused of making a false threat against LAX, authorities said.
The beefed-up patrols were also a precaution on the anniversary of the September 11, 2001, terror attacks, police said. The two other airports are LA/Ontario International Airport in Ontario, California, and Van Nuys Airport in Los Angeles, police said.
"In light of recent events at Los Angeles International Airport involving a disgruntled former airport worker and the 9/11 anniversary tragedy, Los Angeles Airport police has enhanced the deployment of uniformed officers in and around LAX, Ontario and Van Nuys airports.
"Officers will be highly visible on foot, bikes, motors, in patrol vehicles and managing traffic," Los Angeles Airport Police Chief Patrick M. Gannon said in a statement provided by his spokeswoman.
"The safety and security of the traveling public, employees and visitors is our priority and we encourage the traveling public to report all suspicious activity. If you see something say something, security is everybody's business," Gannon said.
Nna Alpha Onuoha, a former Transportation Security Administration employee, made his initial appearance in a federal court in Los Angeles on Wednesday afternoon to face a count of making a false threat and a count of making threats against interstate commerce, said Thom Mrozek, a spokesman for the U.S. Attorney's Office.
At the request of Deputy Federal Public Defender Samuel Josephs, the detention hearing was continued until Monday at noon PT, Mrozek said.
The two charges together carry a maximum sentence of 15 years in prison, he said.
Onuoha, 29, of Inglewood, California, is a former screener with the TSA at LAX, FBI spokeswoman Laura Eimiller said.
On Tuesday afternoon, the FBI received information from the TSA confirming that Onuoha had resigned from his position with the agency, which he had held since 2006, Eimiller said. He was suspended between July 21 and July 27 after he reportedly told a 15-year-old girl that she should "cover up," according to an FBI affidavit filed in court.
After his resignation Tuesday, Onuoha allegedly left a package at TSA's LAX headquarters addressed to a TSA employee, the FBI said.
A bomb squad with Los Angeles Police inspected the package, Eimiller said.
It didn't hold explosives, but it did contain an eight-page letter in which Onuoha expressed his thoughts about the incident that led to his suspension and disdain for the United States, among other opinions, Eimiller said.
Later in the day, a man believed to be Onuoha contacted the TSA by telephone, instructing an employee to "begin evacuating certain terminals at the airport," Eimiller said in a statement.
The caller told the employee that he would "be watching" to see if TSA was evacuating the terminals as he instructed, the FBI said.
A second phone call was received by TSA from a male caller, also believed to have been Onuoha, who again advised the TSA employee that specific terminals at LAX should be evacuated, the FBI said.
Police cleared the terminals, but no threats were found, the FBI said.
At Onuoha's apartment, the FBI's Joint Terrorism Task Force found a note taped inside a closet containing an unspecified threat citing the 9/11 anniversary.
The handwritten message said: "09/11/2013 THERE WILL BE FIRE! FEAR! FEAR! FEAR!" according to the FBI affidavit filed in court.
After waiving his Miranda rights, Onuoha told the FBI that the note referred to how he intended to start preaching in the streets on September 11, 2013, court papers said. He also told the FBI that he didn't intend for the statements in the phone calls to LAX to be threats.
Onuoha was arrested outside Los Angeles, in Riverside, California, by task force members assisted by Riverside police, authorities said.