Ten people have been killed and 10 others injured in a shooting by a student at a Texas high school, says the state governor.
The attacker, who is in police custody on murder charges, was identified as Dimitrios Pagourtzis, a 17-year-old pupil at Santa Fe High School.
He allegedly used a shotgun and revolver apparently taken from his father, who legally owned the weapons.
Most of the dead from the attack in Santa Fe are students, said police.
Texas Governor Greg Abbott said “various kinds of explosive devices” had been found at the school, 40 miles (65km) south of Houston, and off-campus.
These included “a CO2 device” and “a Molotov cocktail”, he added.
The Republican governor said police had found information on the suspect’s diary, computer and mobile phone suggesting he planned the attack.
Mr Abbot said the teenager wanted to take his own life afterwards, but “gave himself up” because “he didn’t have the courage to commit the suicide”.
Santa Fe Police Chief Jeff Powell advised residents to be aware of any suspicious objects they find.
“Do not touch any items that look out of place,” he said.
Santa Fe school police officer John Barnes has been named among the injured. He was in a critical condition and undergoing surgery, according to local media.
Students said the shooter entered an art class and opened fire shortly before 08:00 local time.
“There was someone that walked in with a shotgun and started shooting,” one witness told newsmen, “and this girl got shot in the leg.”