HOUSTON, TX (CNN) — A 17-year-old student was killed and three other students were injured in stabbings Wednesday morning at a Houston-area high school, Harris County authorities said.
The stabbings happened around 7:10 a.m. CT during a confrontation at Spring High School, about 20 miles north of downtown Houston, Harris County Sheriff Adrian Garcia said.
Three students were detained for questioning at the sheriff's office, Garcia said. The names of the students involved in the incident weren't immediately released.
One of the injured students was in surgery late Wednesday morning at a hospital, and two others were at a different hospital with minor injuries. Garcia didn't describe the condition of the patient in surgery.
After the stabbings, students were kept in classrooms for safety and to allow authorities to interview witnesses, said the superintendent of Spring Independent School District, Ralph Draper. The school intended to dismiss students for the day at noon, he said.
Garcia said authorities believe the three students who were detained "are the only persons of interest that we need to have in custody."
The sheriff said that "there has been some information that this may have been gang-related," but he stressed that no conclusions had been reached because the investigation was in the early stages.
Information on what led to the stabbings was limited. Garcia said an encounter between students turned into a physical confrontation involving "cutting instruments of some sort."
Sheila Dauth, mother of a Spring High School freshman, said she learned of the stabbings around 7:15 a.m., when her son texted her. They continued to communicate in the hours after, while he and other students were kept in their first-hour classes, she said.
"He said he's OK. He said it was pretty scary at first when they were rushing everyone into the classrooms," Dauth said. The students have drilled for such situations, "but I don't think he expected to be in a lockdown" like this, she said.
Dauth said she was disappointed that she learned about the incident through her son and the local media hours before the school district contacted her. The district gave automated phone and e-mail messages to parents about three hours after the stabbings, she said.
Draper, while not specifying the time it took to notify parents, told reporters that the district needed to do two things before communicating with families. First was to ensure the rest of the students were safe, and second was to coordinate with authorities so that the investigation wouldn't be compromised.