A motorcyclist was critically injured and his passenger killed following an accident near downtown San Antonio late Sunday night.

It was announced on Monday that the man who was driving that bike -- identified as Juan Alcala, 54 -- has been charged intoxication manslaughter charge.

Witnesses tell police they noticed a motorcycle swerving before it struck a wall at a high rate of speed around 10 p.m. near the I-35 South at South Frio exit.

The passenger of the motorcycle flew over the wall and fell 20 feet to a road below, police said. Her name has not been released.

Alcala skidded for nearly 40 feet before he finally came to a stop.

Alcala and his passenger were taken to San Antonio Military Medical Center, where the passenger was pronounced dead a short time later. 

Neither were wearing a helmet, according to San Antonio police.

Police say Alcala appeared to have been intoxicated.

South frio fatal moto accident