ABC News' Suzan Clarke and Colleen Curry report:

The father of a 9-year-old boy who stowed away on a flight from Minnesota to Las Vegas says he and his fiancée aren't bad parents, questioned how the child could have slipped past security to carry out his plan, and begged for someone to help him handle the boy's behavioral issues.

"I don't have an angel, OK. I have a 9-year-old. To me, he's got a behavior problem," the boy's father, who was not identified in order to protect his minor son's identity, said in an emotional interview Tuesday on WCCO-TV, a CBS News affiliate.

The man said he has been seeking help for his son's behavioral problems since the boy was 5 years old.

"I don't know what to do. I love my son; I'm not giving up on my son. He's just confused. So can anyone please help me? Please," the man said.

Las Vegas Stowaway, 9, Cased Airport Security Ahead of Time

The boy's father said he didn't understand how the boy got onto the Las Vegas-bound Delta flight Thursday at Minnneapolis International Airport.

"You got so much security check at these airports. How can you let a 9-year-old sneak past security, get on the plane without anyone stopping him, questioning him or anything?" he said.

The man said his son left the house on Oct. 1 to take out the trash and didn't come back.

"We didn't think nothing of it," he said. "We thought he was at a friend's house."

When the child didn't come home the next morning, the family called police and learned the boy was in Las Vegas, he said.

Officials said no one noticed when the boy boarded a Las Vegas-bound Delta flight on Thursday at Minneapolis-St. Paul International Airport. His mother reportedly works at the airport.

The boy, who has previously been stopped for stealing a car and repeatedly slipping into a water park, apparently had carefully planned his trip in advance.

According to a report in the Minneapolis Star Tribune, which obtained new details about the boy's trip from an email that was sent to Hennepin County officials, the boy went to the airport on Oct. 2, one day before he boarded the flight, to conduct a "reconnaissance trip." He reportedly took a piece of luggage from the bag claim area, ate at an airport restaurant, and left the bag at the restaurant without paying, the newspaper reported.

The following day, the boy reportedly waited until a large family was going through a TSA security checkpoint and pretended to be part of that family. He was then seen on surveillance video talking to a gate agent, waiting until the agent was distracted, and then walking down the ramp to the plane by himself.

Once the plane took off, airline staff realized that the boy's name was not on a list of unaccompanied minors for the flight, and police met the plane at its destination. They took the boy into custody, at which point he became "violent" and was hospitalized, according to the email.

WCCO reported that the boy was on his way back to Minnesota, and added that the child's father will be getting help for his son from Mad Dads, an organization that promotes positive images of fathers and engages in community and youth outreach.

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