The Miami Herald reports that a college student was arrested on drunk-driving and manslaughter charges after police say he struck two cyclists on a road to Key Biscayne, Florida early Wednesday, killing one and seriously injuring the other before driving off.

Alejandro Alvarez, 21, a University of Maryland student who said he had been out all night at a Miami Beach club, turned himself in after having second thoughts about fleeing, Miami-Dade police said in an arrest affidavit released late Wednesday.

Alvarez returned to the site of the collision some 20 minutes later and, while crying “hysterically,” admitted he had hit the cyclists, police said.