Police say explosives were found on the school grounds
Ten people have been killed and 10 others injured in a secondary school shooting in the US state of Texas.
One person is in custody and a second "person of interest" has been detained after a gunman opened fire at Santa Fe school.
Both of the suspects detained are believed to be students.
The incident reportedly began shortly after 8.00am local time.
Explosive devices were also found by police in the school grounds and surrounding areas adjacent to the school.
Police urged people to be on the lookout for suspicious items and not to approach them.
One police officer was also shot during the incident and is recovering in hospital.
State governor Greg Abbott has been speaking to reporters.
"One of the most heinous attacks that we've ever seen in the history of Texas schools.
"It's impossible to describe the magnitude of the evil of someone who would attack innocent children in a school".
The school was evacuated and students and staff were taken to a local gym to meet with their families.
Police say it is no longer an active shooter situation.
It is not known if those killed are students or staff.
In a statement earlier, school district officials said: "A horrific event occurred today at Santa Fe High School.
"At this time, the campus has been cleared, and the students have been relocated and are in the process of being reunited with their families.
"In this new operational investigation, we know that we have at least six that have been transported including one district police officer that we believe to have been a result of gunshot wounds.
"We have one suspect in custody and one suspect of interest."
Injured students and staff have been transported to local area hospitals.
There are also multiple agencies on site including the FBI, Texas Department of Public Safety and local law enforcement agencies.
Additional reporting: IRN