WASHINGTON—A federal transportation investigator said Tuesday no Texas or U.S. motor safety officers were on duty when an unsafe bus crossed the border hours before a fatal crash.

National Transportation Safety Board investigator Pete Kotowski said the Mexican-made bus was checked by customs and border officers when it came into the United States at a Laredo, Texas, crossing in January.

But because no Federal Motor Carrier Safety Administration or Texas Department of Public Safety inspectors were on duty “no safety inspection was conducted,” Kotowski said.

An NTSB investigative hearing on the crash began Tuesday and was to continue Wednesday.

The bus crashed near Victoria, Texas, killing one man among the 47 passengers. It was returning to Houston from Monterrey, Mexico, when the driver veered off the road and overcorrected, causing the bus to flip on its side and strike a guardrail. Pablo Mendez was killed and his wife and daughter were among dozens of injured passengers.

NTSB regulator Debbie Hersman, who chaired the hearing, said loopholes were used to put a bus that did not meet federal safety standards on the road.

“The operator of this bus went to some pains to register this bus in two states, Texas and California, using false or storefront addresses and a third party to complete the paperwork,” Hersman said.

Additionally, federal government systems that are used by enforcement and registration officials are not adequate to detect which passenger-carrying vehicles fail to meet federal safety standards, Hersman said.

Capricorn Bus Lines Inc. of Houston owned the bus and leased it to International Charter Services Inc., also of Houston.

Capricorn was not allowed to travel out of Texas, but by leasing the bus to International Charter Services, the bus could make the trip into Mexico.

Motorcoach crashes have been in the headlines throughout the year. Initially, many of the bus crashes have been blamed on a missed curve, a fatigued driver or tire problem. But investigations in several crashes have uncovered bigger problems such as poor screening of drivers and bus companies that were shut down but were still operating in the U.S.

Advocates for increased motorcoach safety say the crashes have highlighted gaping holes in regulation of the passenger bus industry and the need for tighter enforcement.