Two women were escorted off an Air Canada plane for refusing to sit in seats that had been vomited on by passengers from a previous flight and still had visible residue.

Susan Benson, a passenger on flight AC1706 from Las Vegas to Montreal, said on social media that she witnessed unfair and unpleasant treatment by Air Canada.

According to the woman's account, when she entered the plane she noticed a "foul" smell that allegedly came from the seats in front of Benson. Although at first it was not clear why, it was later discovered that on the previous flight, someone had vomited in that area.

Passengers who had to sit in these seats complained that both the seat and the seat belt were still wet and had "visible" vomit residue.

"Air Canada attempted a quick cleanup before boarding but clearly wasn’t able to do a thorough clean. They placed coffee grinds in the seat pouch and sprayed perfume to mask the smell," Benson said.

Despite this, the flight attendant told passengers that she could not offer another option due to the flight being full. "The passengers said they couldn’t possibly be expected to sit in vomit for five hours. They argued back-and-forth for several minutes and then the flight attendant said she would get her supervisor," Benson said, adding that it was the passengers themselves who suggested they at least be given towels or blankets to sit on.

However, the pilot spoke with the two passengers who were complaining. "He told the two ladies that they had two choices: they could leave the plane of their own accord and organize flights on their own dime, or they would be escorted off the plane by security and placed on a no fly list," Benson said, highlighting the airline's unfair treatment.

Air Canada later said they are reviewing the case and taking it very seriously. However, they have not yet stated if there will be any compensation for the affected passengers.

"We are reviewing this serious matter internally and have followed up with the customers directly as our operating procedures were not followed correctly in this instance. This includes apologizing to these customers, as they clearly did not receive the standard of care to which they were entitled, and addressing their concerns," the company said, according to Fox Business.