Updated at 6:15 p.m. ET
CYPRESS, TEXAS More than a dozen people were wounded when a suspect went building-to-building in an apparent stabbing attack at a Texas college campus Tuesday, authorities said.
The attack about 11:20 a.m. on the Lone Star Community College System's campus in Cypress sent at least 12 people to area hospitals, including four people taken by helicopter, according Sheriff Adrian Garcia of Harris County. Of the 12 people hospitalized, two people were in critical condition, three people were upgraded from fair to good condition and one was soon released. Two people had refused treatment.
Garcia confirmed that one white 21-year-old male was in custody, which CBS Houston affiliate KHOU identified as Dylan Quick. Witnesses told the police department a man was "on the loose" and attacking people. After reviewing video evidence, police have determined the rest of the student body is safe and that there are no other suspects.
Lone Star officials initially urged people on campus, about 25 miles northwest of downtown Houston, to take shelter and be on alert for a second suspect. But Gilliland said a short time later that authorities believed just one person was responsible. He did not say whether the suspect is a student.
"It was the same suspect going from building to building," Gilliland said.
Gilliland said the attacker is believed to have had some type of knife or a pencil, but authorities could not immediately confirm the weapon used.
Student Teaundrae Perryman said he was in class when he received a text message from a friend and went outside to see a young woman being loaded into an ambulance with what appeared to be stab wounds to either her neck or head. He said he didn't receive an email alert from the college until 11:56 a.m.
"I was concerned but I wasn't afraid because I was with a large group of people," the 21-year-old said, later adding, "The police got to the scene very quickly."
The four people flown by helicopter and two others with moderate injuries were taken to Memorial Hermann Texas Trauma Institute.
One student said she learned one of her classmates was stabbed after leaving the school's Health Science Center building.
"I called to check on another classmate who was still inside the building and she said the classroom was on lockdown and she said one of the classmates had been stabbed," said Margo Shimfarr-Evans told CBS Houston. "It happened in the hallway."
Courtland Sedlachek, 18, was in class when his phone started buzzing along with the phones of everyone else in class. The room was temporarily locked down, but students were let out and off campus a short time later, in what Sedlachek described as an orderly evacuation.
He described his reaction as a "little bit of nervousness."
The attack came three months after a different Lone Star campus was the site of a shooting in which two people were hurt. The suspected gunman in that incident is charged with aggravated assault.
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