A gunman who killed 11 people, including himself, at an adult education centre in central Sweden may have been a student at the school, police said on Thursday, as they described chaotic scenes after the country's deadliest mass shooting as being like an "inferno".

OREBRO, Sweden (Reuters) - Swedish police found three rifles in the adult education centre in Orebro where a gunman killed 11 people and wounded several others this week in the country's deadliest mass shooting, a spokesperson said on Thursday.

The attack on Tuesday - described by Sweden's prime minister as the "worst mass shooting" in the country's history - happened at a school for adults.

By Johan Ahlander and Simon Johnson OREBRO, Sweden (Reuters) -Swedish police found three rifles near the body of the gunman amid a chaotic scene they described as an "inferno" after 11 people were killed and several wounded in the country's deadliest mass shooting,

Swedish police said the gunman in the country’s worst mass shooting was connected to the adult education center where he opened fire Tuesday, killing 10 other people. Police later found him dead.

Police investigating Sweden's worst mass shooting were still trying to establish a motive as to why a lone gunman opened fire at an education campus in the southern city of Orebro, killing 10 people.

Swedish police confirm around 10 people were killed at a school for adults on the outskirts of Stockholm. The gunman is believed to be among the dead.

Around 10 people were killed in a school shooting in Örebro. The damage at the crime scene was so extensive that investigators were unable to be more definitive, said Roberto Eid Forest, head of the local police.

Police say 10 people have been killed in a shooting at an education centre in central Sweden, including the suspected gunman. Prime Minister Ulf Kristersson described Tuesday's attack at Risbergska school in Orebro, 200km (124 miles) west of the capital city Stockholm, as the "worst mass shooting in Swedish history".