MADISON, AL -- A 14-year-old boy has been shot in the head while walking down a hallway in Discovery Middle School, HEMSI officials said.

The boy, whose name has not yet been released, is in "extremely critical condition," said HEMSI Chief Operations Officer Don Webster.

Police are reporting that they have the suspect in custody.

Madison Mayor Paul Finley said the school has been put on lockdown, but all other students are safe. Finley has asked parents not to come to the school at this time.

Read all of our coverage and the latest news on the Discovery Middle School shooting

Latest news:

Victim dies, police identify him as 14-year-old Todd T. Brown

Shooter, another ninth grade student, to be charged with murder

Madison school shooting: Witness said she thought gunshot was balloon popping

Student describes terror inside Discovery Middle School after Madison school shooting

Video of the

Videos of the

Photo slideshow:

Witness:

Editor's note: An earlier version of this post said the victim was a 15-year-old boy. Police later said the boy, Todd T. Brown, is 14 years old.