United Airlines has come under fire again after leaving a Canadian teenager behind at an airport in Connecticut, according to CTV News Vancouver. The 15-year-old boy, who attempted to board a flight home to Vancouver International Airport (YVR) on Tuesday, was reportedly left stranded at Bradley International Airport near Hartford for almost 10 hours. 

A United employee informed Victor Shmulevich that the airline doesn't allow unaccompanied minors to board its flights. The teen's parents made alternative plans for him to return to Vancouver, British Columbia. 

Read: Canada Will Punish Airlines For Treating Passengers Badly

Shmulevich's father arranged for him to board a flight with Air Canada, which allowed him to fly to Toronto and then to Vancouver, according to Vancouver news outlet Georgia Straight. Shmulevich reportedly arrived 20 hours after the United Airlines incident. 

Shmulevich's father told CTV News Vancouver "what's most concerning is that [United] didn’t actually try to assist us. They said, 'Sorry, you've got to deal with this by yourself. We can't do anything."

A media representative from United Airlines issued a statement Tuesday to International Business Times about the incident. The airline explained its strict policy against boarding unaccompanied minors, however, United also plans to investigate how Shmulevich was able to obtain a ticket for a flight that wasn't included in its unaccompanied minor program.

"United does not allow unaccompanied minors to travel on itineraries with connecting flights, which was the case in this instance," the representative wrote. "We are looking into the booking process further to determine how this passenger was able to purchase a ticket for a flight that was not part of our unaccompanied minor program."

"The safety of our passengers is our number 1 priority. However, we were not made aware of this situation by the passenger or the airlines. We are looking into this issue and will be reviewing appropriate protocols with the airlines," Kevin Dillon, executive director of the Connecticut Airport Authority, told IBT in an email.

Read: Teen Arrested After Jumping Off Copa Airlines Flight, Other Similar Incidents

The Los Angeles Times reported on changes made to United Airlines unaccompanied minor program in 2014. United initially required children between ages 5 and 12 years to participate in the program, but it was modified to include minors up to the age 15. United spokesperson Charles Hobart told the Times, "we made a thoughtful review of the policy and decided that this change will provide the best possible care for these travelers."

Minors traveling solo with United will be forced to pay an additional $150 alongside the original ticket, according to the airline's website. The fee is required for each direction of travel in domestic and international territories. United collects the additional fee for the "extra handling" needed to care for children traveling alone.

United's unaccompanied minor policy claims to "understand just how important it is to provide a safe, comfortable, fun experience for children who are flying alone." The airline believes its unaccompanied minor service provides "peace of mind" for parents. Benefits to enhance the unaccompanied child's experience include early boarding, a seat towards the front of the aircraft and a complimentary food item.

United Airlines isn't the only company to enforce strict unaccompanied minor regulations. Southwest Airlines requires children ages 5 to 11 to enroll in its unaccompanied minor program, which charges $50 fee in each direction. Delta Air Lines also has an unaccompanied minor program for children ages 5 to 14, which requires a $150 fee. Delta's program is optional for children between 15 to 17. 

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