A police Taser gun was used against a 14-year-old boy spotted walking the streets with what looked like a sword.
The teenager is the youngest person Thames Valley Police has ever used a Taser gun against.
A force spokesman said officers know the decision to use a Taser should be based on the risk the person poses, and not on their age.
It was feared the youth seen in Blackbird Leys in Oxford on Tuesday morning was "a threat to the public".
A large pruning saw has since been found near the scene of the arrest.
A police spokesman told the BBC News website that the 14-year-old was the youngest person the force had used a Taser against.
He said of the decision to use a Taser on a youngster: "It's not a question of age but the risk that the person poses to others or themselves."
A spokeswoman for the Association of Chief Police Officers said: "We do collect information on the use of Tasers but we don't record the age because it does not make any medical difference.
"Just anecdotally speaking, off the top of our heads, it does look like the youngest in the country."