Subway suspect in custody

I did promise an update, so here goes. The man who bludgeoned 20-year-old Dewayne Taylor on a SEPTA subway train last Thursday surrendered to a city mental institution earlier today, police sources told the Daily News.

The attacker will be released to police pending a psychiatric evaluation. Once the cops have him, the man -- whose name has not yet been released -- will be charged with attempted murder, aggravated assault and related offenses.

Dewayne and his mom spoke with us earlier tonight. Their story will be in tomorrow's Daily News.

And for those who have e-mailed or commented that there was an unspoken motive behind the attack, it appears you'll be disappointed. Investigators said they still believe the attack was the random work "of a mentally unstable man."