Police are hunting for two suspects, one of whom is believed to have been carrying a sword, following an altercation that left a teenager injured.
Armed police were called to the incident near St Peter's High School in Gloucester earlier. The school and Willow Primary Academy were put into lockdown while officers searched for the group who had fled the scene.
A woman has been arrested on suspicion of assisting an offender and remains in custody, but officers are still hunting for the two men who were reportedly chasing two boys.
Officers remain outside both schools, but all pupils have now been sent home.
A 17-year-old boy sustained a superficial wound believed to have been caused by the sword, said police. Police initially said he was taken to hospital, however this was not correct.
Another victim, also 17, was not injured.
Police described both suspects as white males. One is aged in his late teens to early 20s, of a medium to large build, and about 6ft tall. He was wearing white sliders at the time of the incident.
The other suspect is described as being about 5ft 5ins tall, of slim build and wearing black clothing.
St Peter's High School pupil Jimmy said the situation was "really scary" and he was still in shock.
After getting into the Tuffley school for the day, he said his friends came in and told him something had happened near his home.
He said the school's alarm then went off and the computer he was on displayed a message saying "This is a lockdown".
"The computers are not accessible at all and we've all had to turn the lights off, lock the doors, turn all the blinds down, and we've had to get on the ground," he said.
"At the time I was scared. My heart was racing," he added.
Jimmy said pupils were locked in their classrooms for two to three hours.
"[When police cars arrived] I thought this is getting serious, I'm getting worried, I don't know what's going on," he said.
The 15-year-old said he was able to message his mother when the school let students use their phones after about an hour.
"When I was able to eventually get out, she was giving me a bunch of hugs," he said.
"What I am is shocked. I'm surprised that this happened," he added.
Jimmy said the school had previously run lockdown drills but a real event had never happened before.
Adam, whose daughter attends the same school, said he felt frightened even though he had texted her and knew she was OK.
"I don't think this should happen at school. Thank God she is safe," he said.
The school had messaged parents to say everything was under control, he added.
Another parent outside the school gates earlier, whose daughter is in Year 8 and nephew is in Year 7, said the family was "so worried".
"I'm slightly calmer now the police have told us they're safe but I want to take them home."
"I haven't heard from them because they aren't allowed phones in school," she added.
Addressing parents outside St Peter's High School, an officer said a police presence would remain at the site for the rest of the school day.
"That is not there for a safety reason, it is to provide reassurance to yourselves and answer any questions. It is not because there is any risk or threat to anyone," she said.
Det Insp Sophie Dawkins, from Gloucestershire Police, said she understood the concern "this incident would have caused, especially when it happened near a school at drop off time".
"We've had armed officers searching the area, along with support from our drone unit and the National Police Air Service, and work is ongoing to identify and locate those involved," she added.
Dawkins said "numerous" inquiries had been taking place.
"We are now keen to hear from anyone who has not already spoken to police who witnessed what happened or who has dashcam or any other footage," she added.
Alex McIntyre, Gloucester's MP, said his thoughts are with "the young person who was injured and their family".
"I have also been in contact with the Department for Education who stand ready to provide any support necessary to St Peter's," added McIntyre.
Lorraine Campbell, an independent councillor who represents the Tuffley area, said although police stressed there was no ongoing risk, the incident was still "very concerning" and there was "a great deal of uncertainty".
"There is always a big shock when we hear of something happening very literally on our doorsteps, it's of great concern. Hopefully it gets sorted out as soon as possible," Campbell said.
"Anything like this is extremely troubling and disturbing - we are all concerned but we do all stand together on these things," she added.
