Four people were killed and 19 injured when a Tufesa bus rolled over the side of a bridge in Sonora on May 31, 2016 at approximately 4:00 a.m. Three people died in the crash and a fourth later died in a hospital. All of the victims were Mexican nationals.

The accident, which occurred on Mexico highway 15 north of Guaymas, Sonora, was allegedly caused by the driver falling asleep at the wheel.

The Tufesa passenger coach had initiated its scheduled route in Los Angeles and was traveling to Sonora and Sinaloa, also passing through the Arizona cities of Phoenix and Tucson. There were 24 people on board the bus, including the driver and an assistant driver.

I have traveled many times on Tufesa buses and found the drivers and service to be very professional. However, of late the bus line has apparently gotten a reputation among some Sonorans as sometimes being reckless.

And since the accident, Sonoran drivers have posted videos of Tufesa buses driving on the highway at excessive speeds or with an apparently distracted driver behind the wheel.