Update: Suspect in custody after bicyclist, good Samaritan killed in crash Tuesday

A suspect is in custody after a bicyclist and a woman who tried to help him died during two separate collisions Tuesday night in Port Huron Township.

According to a media release, the St. Clair County Sheriff's Department identified a suspect vehicle responsible for hitting the good samaritan — a light-colored Lincoln — as of late afternoon Wednesday. Authorities said that the suspect who is being investigated is also being held at the county jail on an unrelated warrant.

The sheriff's department posted on social media that a 30-year-old Marysville man called 911 at about 10:30 p.m. Tuesday to report he had hit a bicyclist in the 3700 block of Dove Road in the township.

A 40-year-old woman living nearby came to the scene to help and was reportedly hit by the Lincoln.

The woman and the bicyclist, a 56-year-old Fort Gratiot man, were pronounced dead at the scene.

The driver who called 911 remained at the scene and is cooperating with the investigation, according to the sheriff's department.

The driver of the second vehicle involved fled.

Anyone with information regarding this incident is asked to contact the detective bureau at (810) 987-1711.