SANTA FE (AFP) - The latest mass shooting at a US school unfolded Friday (May 18) in the Texas town of Santa Fe, where 10 people were killed by a heavily armed student.

The tragedy occurred three months after the massacre in Parkland, Florida, where a former student entered a high school and killed 17 students and staff.

What happened

Police said a 17-year-old student, Dimitrios Pagourtzis, burst into a classroom and opened fire at Santa Fe High School, about 30 miles (50 kilometres) southeast of Houston, as the school day was beginning around 8.00 am.

Authorities said 10 people were killed and another 10 injured, as students fled in panic, seeking shelter in nearby homes or shops for safety, or lining up on school fields as the injured were taken away in ambulances.

Harris County Sheriff Ed Gonzalez said the "majority" of the 10 dead were students. Area residents said two of the 10 wounded were in critical condition.

The Houston Chronicle said Pagourtzis was armed with pipe bombs in addition to firearms.

Texas Governor Greg Abbott said searches of two residences had turned up "various explosive devices" including a "CO2 device" and a Molotov cocktail.

The shooter

Pagourtzis, a Grade 11 student at the school, was taken into custody on murder charges.

Police said he was carrying a shotgun and revolver legally owned by his father under a long coat when he opened fire on fellow students.

Abbott said journal entries by the suspect suggested he wanted to commit suicide but that "he gave himself up." Abbott also said there were no "warning signs" about the suspect ahead of time although he did post a picture on his Facebook page of a T-shirt with the words "Born to Kill" on it.

Law enforcement authorities were questioning two "people of interest," the governor said.

Political reaction

US President Donald Trump expressed "sadness and heartbreak" over what he called an "absolutely horrific" incident - the second mass shooting in Texas in six months - and ordered flags to fly at half staff on all public buildings.

Trump, who has favored arming teachers, acknowledged that "this has been going on too long in our country." "My administration is determined to do everything in our power to protect our students, secure our schools, and to keep weapons out of the hands of those who pose a threat to themselves, and to others," he said.

Survivors of February's high school shooting in Parkland, Florida voiced solidarity and vowed to press on with their campaign for tighter gun laws.

The victims

Among the dead were two teachers: Ann Perkins, known to many as "Grandma Perkins," the Houston CBS TV affiliate reported; and Cynthia Tisdale, a mother of four who taught "because she loved to help children," her son Recie Tisdale told The Washington Post.

Also among the dead was Sabika Sheikh, an exchange student from Pakistan in Texas as part of the State Department-run Youth Exchange and Study (YES) Program, Pakistan's embassy in Washington said in a statement.

Her father, Aziz Sheikh of Karachi, told the Los Angeles Times that his daughter was a "brilliant student" and "the lifeline of our family." She was only weeks away from returning home, and her death unleashed an outpouring of sympathy in Pakistan.

Family members told the Houston Chronicle that the dead also included Angelique Ramirez, 15; Chris Stone, 17; Jared Conard Black, 17; and Shana Fisher, who turned 16 on May 9.

An ABC affiliate listed Aaron Kyle McLeod as a victim, and CBS said Christian Garcia had also been killed.

Kimberly Vaughan died as well, her mother Rhonda Hart wrote on Facebook, adding, "We need gun control. We need to protect our kids." Among the 10 people wounded was school security officer John Barnes, 49, who was hit in both arms while confronting the shooter. A former Houston police officer, he had joined the school district in January. He was listed in stable condition.

Rome Shubert, 16, a student at the school, said he was in art class when he heard a loud bang.

"I was shot in the back of the head but I am completely okay and stable," he tweeted.

"This shouldn't happen to anybody," Shubert told ABC affiliate KTRK. "Nobody deserves that."