The incident occurred after the end of the school classes.
Governor Kay Ivey also reacted on Twitter, taking a moment to condemn guns in schools. "I'm saddened to learn of the death of the Huffman student".
Meanwhile, the Congress of Florida voted a bill limiting access to firearms.
The shooting comes as tension is high in schools after a gunman with an assault-style rifle killed 17 people at a high school in Parkland, Florida, on February 14.
Arrington was given CPR at the scene and en route to the hospital, but the efforts to revive her failed. Birmingham Police Chief Orlando Wilson said the shooting left a 17-year-old girl dead and a 17-year-old boy wounded. Both were rushed to UAB Hospital in separate Birmingham Fire and Rescue Service trucks.
Lt. Peter Williston, spokesman for the Birmingham Police Department, said "no information will be released on that individual, pending a review of the case by the Jefferson County District Attorney's Office".
Birmingham's Mayor Randall Woodfin said, "We lost a person, not just a person, but a student".
Community leaders reacted to the news of the shooting on social media. "We'll give you the answers as they come".
Sources said a male student was "showing off" his gun when it discharged, striking the female student.
The Alabama school has working metal detectors and would be open on Thursday with heightened security and a crisis team on hand, Lisa Herring, superintendent of Birmingham City Schools, told reporters. A school employee was being evaluated at the scene, but it was not clear if that staff member was shot, the newspaper reported. Parents are heartbroken to hear the news of Courtlin Arrington getting shot and losing her life. She said those involved in the incident are "good students". I'm praying for the family of this young lady who tragically lost her life way too early.
Huffman is one of seven public high schools in Birmingham, the state's most populous city.