Several people were killed in a school shooting in Sweden on Tuesday, daily Aftonbladet and broadcasters SVT and TV4 reported, citing anonymous sources.

A police spokesman said he could not comment on the information that several people had been killed.

Ambulances, rescue services and police are onsite, a spokesperson for local rescue services said.

The shooting took place in a campus area where several schools, for both children and adults are located.

Police said students were held indoors at the affected school and also at nearby schools.

"The news of an attack at Orebro is very serious," Justice Minister Gunnar Strommer told public broadcaster SVT, adding that the government was in close contact with police.