I speak Spanish and here's (in short) what the article says:
Matamoros, Tamaulipas - A bike ride called "Matamoros to Bagdad Beach" ended this Sunday morning in tragedy when a driver drove into its lead group. Early reports said that it happened a little after 8:00am. 500 people participated in the race overall. 15 of them were involved in the crash. The club that ran the race is called “Camaleones” and this was the third time the race has been run.

When the lead group got to 16k, the driver swerved across the road and struck them. 34 year old Alejandro Álvarez from Brownsville was killed. The rest of the riders had various fractures and road rash. All were treated at Matamoros Hospital. The driver, Juan Campos, was arrested has been tested for drugs and alcohol.