Sexual assaults on commercial flights could be on the rise, and there may be even more than available statistics suggest, according to the federal government.

The FBI announced Wednesday that it receives reports of mid-air assaults "at an alarming rate," with a steady rise in the number of investigations each year since 2014.

FBI representatives revealed during a press conference Wednesday that the FBI opened 63 investigations into mid-flight sexual assaults in 2017, up from 38 in 2014. There was a steady rise in each interim year, with 40 in 2015 and 57 in 2016, according to CNN

Some of the FBI’s comments can be seen in video form below, courtesy of ABC reporter Sam Sweeney.

The perpetrators of these assaults tended to act during overnight, red-eye flights or any flights where the cabin lights would be dimmed for customer comfort. Victims are commonly seated away from the aisle, either in the middle of the row or by a window. According to the FBI, many of the victims are asleep at the time of the assaults.

Special Agent David Rodski said he was “shocked” that more passengers do not promptly report assaults during flights, usually waiting until the plane is on the ground, if at all. However, that lines up with reporting data on sexual assaults in other contexts. Only a little more than 30 percent of rapes are reported to police, with even less resulting in arrests or convictions, according to RAINN.

plane Sexual assaults in commercial flights are on the rise, according to the FBI. An Airbus A380 takes off from Filton Runway on February 1 2008 in Bristol, United Kingdom. Photo: Matt Cardy/Getty Images

A union survey of flight attendants found that authorities were contacted after fewer than half of reported in-flight assaults, similar to how often it happens out of airplanes. The FBI conceded that the actual number of assaults could be higher than the numbers it presented on Wednesday suggest.

The federal government does not specifically track assaults on commercial flights, according to a December 2017 report from CNN.

Flight attendants are not trained to deal with sexual assaults on flights. The FBI said it would work to “raise awareness” of the issue, but as it stands, the first responders for these assaults are not prepared to deal with them.