UPDATE: SANTA FE, TX - Authorities have identified the suspect in Friday's shooting at Santa Fe High School that killed nine students and one teacher at a Texas high school.

NBC News reported that law enforcement has identified the suspect as 17-year-old Dimitrios Pagourtzis.

Harris County Sheriff Ed Gonzalez said that the suspect and another person being questioned in connection with the shooting are are students at the school.

Gonzalez said a majority of those that were killed in the shooting were students. He said a Santa Fe Independent School District police officer was critically injured in the shooting.

Officials at UTMB Hospital in Galveston said the facility had received at least three patients from the scene, including the Santa Fe ISD police officer, a 16-year-old boy and a middle-aged woman. The officer is listed in critical condition. The two others suffered gunshot wounds to the leg and are listed in good condition.

A search of the school is ongoing, Gonzalez said.

Santa Fe ISD officials said in tweets that explosive devices were found at the school and at off-campus locations:

"Possible explosive devices have been located at the school and off campus. Law enforcement is in the process of rendering them safe. School has been evacuated. Call 911 if you see any suspicious item.

"There have been explosive devices found in the high school and surrounding areas adjacent to the high school. Because of the threat of explosive items, community members should be on the look-out for suspicious packages and anything that looks out of place."

Several law enforcement agencies were at a home on State Highway 6, about three miles away from the school. A Harris County deputy at the scene said, "there's a bomb" at the house, according to KPRC2 reporter Jake Reiner. A bomb squad is at the scene, Reiner said.

KPRC2 reporter Joel Eisenbaum said multiple law enforcement agencies were also at another home in a neighborhood about four miles away from the school. It was not immediately clear if that home was connected to the shooting.

The school is located on State Highway 6 near Morning Glory Drive.

The Texas Department of Transportation tweeted that drivers should avoid the highway near the school as police have the roadway blocked.

Texas Gov. Greg Abbott has ordered flags be flown at half-staff in honor of the victims of the shooting.

The following statement about the shooting was released by Santa Fe ISD officials:

"This morning an incident occurred at the high school involving an active shooter. The situation is active, but has been contained. There have been confirmed injuries. Details will be released as we receive updated information. Law enforcement will continue to secure the building and initiate all emergency management protocols to release and move students to another location. All other campuses are operating under their regular schedules.

"At this time, students from the high school are being transported by SFISD transportation to the Alamo Gym located at 13306 Highway 6. Parents may reunite with their students at this location.

"The district will continue to keep you updated as information is available. Safety and communication are our top priorities."

Students, parents recall shooting
One student said that he heard as many as eight gunshots. Another student reported hearing several gunshots before hearing alarms and being told to evacuate.

"I was sitting in my classroom and I heard really loud booms, but I really didn't know what they were at first," student Dakota Scrader said. "Then, I realized what they were when I heard screaming."

"I never thought it would happen here," said Tyler Turner.

"It hurts my heart to see this happening," another student said. "I don't feel safe in this town anymore ... There was nothing we could do but run."

Parents were gathering at a nearby gas station where they were trying to connect with their children.