Two-time NASCAR Cup Series champion Kyle Busch was detained and then arrested in Mexico in January after authorities at an airport found a handgun in his bag. Busch was nearing the end of his vacation with his wife Samantha at the time.

According to the 37-year-old driver, he was going through airport security screening to board a private jet to leave the country after a vacation when he realized he accidentally brought his firearm in his luggage.

Mexico Prosecutor General’s office, in a statement, said that a man originally from Nevada identified as “Kyle Thomas B” was “credited with full responsibility in the commission of the crime of carrying a firearm without a license and possession of cartridges for the exclusive use of the armed forces.”

Busch was arrested on Jan. 27 and sentenced Monday to 3.5 years in prison and fined $1,100, the prosecutor general’s office said.

The 37-year-old issued a statement saying he said that he does “adhere to all handgun laws,” but also admitted in the same statement that he was unaware of the Mexican law that forbids the possession of a weapon in the country without Mexican approval.

“In late January, Samantha and I enjoyed a several day vacation in Mexico,” Busch said. “When departing the country, my handgun was flagged during routine screening at the airport. I have a valid concealed carry permit from my local authority and adhere to all handgun laws, but I made a mistake by forgetting it was in my bag.

“Discovery of the handgun led to my detainment while the situation was resolved. I was not aware of Mexican law and had no intention of bringing a handgun into Mexico.”