The NAACP has issued a warning to black travelers about flying with American Airlines, following what the US’s oldest and most well-known civil rights organization called a series of “disturbing incidents”.

The group said it had issued a “national travel advisory” in response to what it described as “disrespectful, discriminatory or unsafe conditions” for African Americans traveling on the world’s largest airline.

“The NAACP for several months now has been monitoring a pattern of disturbing incidents reported by African American passengers, specific to American Airlines,” the organization said in a release.

“In light of these confrontations, we have today taken the action of issuing national advisory alerting travelers – especially African Americans – to exercise caution, in that booking and boarding flights on American Airlines could subject them disrespectful, discriminatory or unsafe conditions.”

The airline, which serves 500,000 passengers daily, said it was “disappointed” to learn of the advisory.

“We do not and will not tolerate discrimination of any kind,” CEO Doug Parker wrote in a memo to employees. “We have reached out to the NAACP and are eager to meet with them to listen to their issues and concerns.”

The first of the four cases cited by the NAACP appears to involve a flight boarded by the Rev Dr William Barber, a civil rights activist and president of the NAACP’s North Carolina branch. The Barber case is already the subject of a pending lawsuit.

Barber says he was kicked off an AA flight in 2016 after responding to two verbally abusive white passengers, who were allowed to remain on the flight.

“This differential treatment was based on race, as other passengers noted and stated to American Airlines employees,” the lawsuit says. “Reverend Barber was calm, complied with all directives from the flight crew, and did nothing that remotely warranted being ejected from the airplane.”

According to the lawsuit, a black airline employee at the gate told Barber that “this tends to happen a lot”. She said she was “sick of American Airlines doing this”.

Barber did not respond to a request for comment at time of publication.

Two of the other incidents cited by the NAACP occurred earlier this year. Briana Williams, 24, said she was booted off an AA flight in August after she asked for her gate-checked stroller during an extended travel delay as passengers were leaving the plane.

“I told a crew member that I was not going to be leaving the aircraft without my stroller,” Williams told the New York Daily News.

The pilot was called, and according to Williams he became angry and summoned police to eject her.

Similarly, Tamika Mallory, the national co-chair of the Women’s March movement, said that after she contested a seat change with gate attendants, the flight’s pilot, who overheard the discussion, kicked her off a flight last week.

“It definitely was white male aggression. I was singled out, I was disrespected, and he was trying to intimidate me,” Mallory told the New York Daily News. “I was discriminated against.”

Unlike when the NAACP issued an advisory in June for black Americans traveling in the state of Missouri, Tuesday’s announcement did not include any qualitative data to support a targeting of black Americans. The NAACP did not respond to a Guardian request for any such information.

“The growing list of incidents suggesting racial bias reflects an unacceptable corporate culture and involves behavior that cannot be dismissed as normal or random,” said NAACP president and CEO Derrick Johnson.

“We expect an audience with the leadership of American Airlines to air these grievances and to spur corrective action.”