Jail records show that he's still in custody at the moment, though there are no other details at the moment. KRON 4 is reporting he was arrested for felony domestic violence. The 49ers corner is being investigated for a felony domestic violence charge.
Police say that Brock went to the station voluntarily and was then booked into the Santa Clara County main jail later on that evening.
Brock, 28, started every game last season and had one interception for a defense that allowed the most points and touchdowns in franchise history.
Police described the woman's injuries as "minor" and she received no medical attention.
The 49ers originally signed the 28-year-old as an undrafted free agent in 2010 out of tiny Belhaven University, an NAIA school.
The incident is said to have taken place less than a mile from the team's Santa Clara headquarters and Levi's stadium.
The team has yet to make a statement on Brock's arrest. More information will come out as the investigation continues. This is the first such incident head coach Kyle Shanahan and GM John Lynch have been forced to deal with, and their reaction will be scrutinized.