Officials have said Dylan Quick was charged with three counts of aggravated assault with a deadly weapon — charges filed for the three most severely wounded of 14 victims.
The campus shut down Tuesday, but will reopen Wednesday.
Quick was born deaf and received a cochlear implant at age 7, CNN affiliate KPRC reported. An article on how he overcame challenges early in life appeared on a Lone Star student blog the first week of April.
Quick told investigators he had fantasies of killing people and had been planning the attack for some time, sheriff’s officials said late Tuesday. Quick used “a razor-type knife” to stab his victims, they added.
CNN’s Ed Lavandera and Jason Morris contributed to this report.