(CNN) The top executive of Napa Valley Wine Train apologized to members of a book club who said they were humiliated when staff booted them from the luxury rail car for disturbing passengers with their laughter.

"The Napa Valley Wine Train was 100% wrong in its handling of this issue," CEO Anthony Giaccio said in a statement. "We accept full responsibility for our failures and for the chain of events that led to this regrettable treatment of our guests."

The apology stems from a Saturday wine tour that went sour for 11 women of "Sistahs on the Reading Edge," a book club from Antioch, California, consisting mostly of black women.

The excursion appeared to start well. Member Lisa Johnson shared giddy photos and video on social media of the women raising glasses of red and enjoying cheese plates against the scenic backdrop of northern California.

Less than two hours after leaving the station, Johnson posted a photo of a woman with a caption that began, "we have a problem."

"We sipped wine, enjoyed each others' company but our trip is being cut short," she wrote. "This woman said our laughter annoyed her because this is 'not a bar'... if we all laugh at the same time it's loud! When we get to St. Helena they are putting us off the train."

Adding insult to injury, the staff "paraded" them through five cars full of passengers to exit the train, Johnson told CNN affiliate KRON. Police met them at the train stop, where they waited for 20 minutes for a bus to pick them up.

Johnson attributed the treatment to racial bias, suggesting in a Facebook post that their only offense was "laughing while black."

"I have been a black woman all of my life and I know exactly what it feels like and that's exactly what it feels like to me."

As news of Johnson's claims traveled, criticism flooded the tour company's Yelp page and the hashtag #laughingwhileblack spread through social media.

A spokesman apologized over the weekend, saying racial bias did not play a role in the treatment. But the women said the apology missed the point.

"They're not apologizing for parading us down those five train cars and giving us to the police; they're not apologizing for making us stand in the dirt for 20 minutes in the hot sun with an 85-year-old senior and somebody else who is just recovering from surgery," Johnson told KRON.

"They're not apologizing to how we felt we were treated on their train," she said. "We feel like we were never their customers, and they never ever made accommodations for us. It was about us having to make accommodations for other people."

In a post that has been deleted from Facebook, the company said the women were asked to leave after becoming unruly.

"Following verbal and physical abuse toward other guests and staff, it was necessary to get our police involved," said the statement, which Johnson shared on Facebook . "Many groups come on board and celebrate. When those celebrations impact our guests, we do intervene."

Giaccio, the CEO, later apologized for the Facebook post, saying it did not reflect events as they occurred.

"In the haste to respond to criticism and news inquires, we made a bad situation worse by rushing to answer questions on social media. We quickly removed the inaccurate post, but the harm was done by our erroneous post," he said in a letter to the women.

Giaccio also apologized for not doing more to accommodate the women even though they had notified the company of the size of their party.

"Clearly, we knew in advance when we booked your party that you would be loud, fun-loving and boisterous," he said. "You told us during the booking process that you wanted a place where your club could enjoy each other's company. Somehow that vital information never made it to the appropriate channels and we failed to seat your group where you could enjoy yourself properly and alert our train's staff that they should expect a particularly vibrant group."

Napa Valley Railroad Police Chief Jeff Hullquist said the women were removed because there was nowhere else to seat them on the full train. He also said the long walk was necessary given the limited number of entry points on the train. It is also customary for police to wait with passengers until transport arrives, he said.

Still, Giaccio acknowledged his staff could have handled the situation better.

"We were insensitive when we asked you to depart our train by marching you down the aisle past all the other passengers. While that was the safest route for disembarking, it showed a lack of sensitivity on our part that I did not fully conceive of until you explained the humiliation of the experience and how it impacted you and your fellow book club members."