At least two people were killed and six others, including students, were injured in a shooting at a school in the US state of Wisconsin, said police.

The shooting took place at Abundant Life Christian School, which serves from kindergarten to grade 12, in the city in Madison in the Midwestern state. The shooting took place in the final week before the holiday break, when people traditionally gather to eat special meals, exchange gifts, and spend time with family and friends.

“Today is a said, sad day, not only for Madison but for our entire country,” Madison Police Chief Shon Barnes told a press conference.

"Every child, every person in that building, is a victim, and will be a victim forever. These types of trauma don't just go away,” he added.  

The shooting killed a teacher and a student. The suspected shooter, who was a student, is also dead.

Madison police said the earlier death toll of five, which was announced during a press briefing, was "erroneously shared".

"Again, three people are deceased. Nine in total were injured, including the three deceased," said the police on Facebook.

President Joe Biden has been briefed on the school shooting, a White House spokesperson said.

"Senior White House officials are in touch with local counterparts in Madison to provide support as needed," deputy press secretary Emilie Simons said in a statement.

For years, the US has become notorious for deadly school shootings on a regular basis, some taking dozens of victims, with many members of the public decrying the lack of tighter gun control to stop more children from dying.