A Norwegian newspaper says the man suspected in the bomb blast that tore apart buildings in the heart of Oslo and in a shooting spree at a youth camp bought six tons of artificial fertilizer some 10 weeks before the attacks.

Verdens Gang newspaper cites Oddny Estenstad, a spokeswoman for agricultural material supplier Felleskjopet, who says the products were delivered to the suspect on May 4.

Artificial fertilizer is highly explosive and can be used in homemade bombs.

Estenstad says police were alerted to the purchase after it emerged the man was suspected of the deadly attacks.

Estenstad didn't answer phone calls seeking comment Saturday. In total, 91 people have been confirmed dead in the bombing and shooting massacre.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

SUNDVOLDEN, Norway (AP) _ Police have detained a man outside a hotel where Norway's prime minister was meeting families of shooting victims. The man told reporters he was detained "because I have a knife."

The man, who appeared to be around 20 years old, was standing outside the hotel next to reporters when two officers apprehended him and led him to a police car.

The man told reporters he was a member of the Labor Party's youth wing and was carrying a knife "because I feel unsafe."