In a statement issued by the White House, Biden said: "Today, families in Madison, Wisconsin, are grieving the loss of those who were killed and wounded at Abundant Life Christian School. It’s shocking and unconscionable."

"We need Congress to act. Now," he said.

He said it was unacceptable that children across the USA could not be protected from gun violence.

"We cannot continue to accept it as normal. Every child deserves to feel safe in their class room," he said.

"My administration has taken aggressive action to combat the gun violence epidemic. We passed the most significant gun safety legislation in nearly 30 years, I have taken more executive action to reduce gun violence than any other President in history, and I created the first-ever White House Office of Gun Violence Prevention. But more is needed," he said.

What happened in the school?

A teen student opened fire inside a classroom at a school in  Wisconsin on Monday which left a fellow student and a teacher dead.

The attacker then turned the gun towards herself and shot herself dead.

The incident happened at Abundant Life Christian School.

Madison Police identified the shooter as 15-year-old Natalie Rupnow.

"She was a student at the school, and evidence suggests she died from an apparent self-inflicted gunshot wound," the police said in a statement.

"A teacher and a teenage student were pronounced dead at the school," the statement said.

The victims were pronounced dead at the school.

"Six other people were injured during the shooting and taken to area hospitals. Two students remain in critical condition and have life-threatening injuries," police said.

The latest school shooting incident occurred just weeks before US President-elect Donald Trump took charge of the office.