A bomb exploded Saturday outside an Italian high school named after a slain anti-Mafia prosecutor, killing a teenage girl and wounding several other classmates, officials said.

The device went off a few minutes before 8 a.m. local time in the Adriatic port town of Brindisi in the country's south just as students milled outside, getting ready for class at the Morvillo-Falcone vocational institute. The school is named in honour of prosecutor Giovanni Falcone and his wife, Francesca Morvillo, a judge who was also killed in a 1992 highway bombing in Sicily by the Cosa Nostra.

The victim was identified as 16-year-old Melissa Bassi, from the nearby town of Mesagne, the town's mayor Franco Scoditti said.

One of the wounded students, a girl walking with the victim outside the school, was reported to be in critical condition after surgery. Officials said at least seven students were injured, but some news reports put the figure at 10.

Dr. Paola Ciannamea, a Perrino physician who helped treat the injured at the hospital, told reporters that one of the injured was a teenage girl who was in a grave but stable condition after surgery. She added that surgery was still being performed on others who suffered burns in the blast.

There were no immediate claims of responsibility for the attack.

Italy has been marking the 20th anniversary of the attack on the Sicilian highway that killed the prosecutor and his wife, but it was unclear if there was an organized crime link to Saturday's explosion.

Fuel used, not dynamite

“It's pure terrorism," said Italy's national anti-Mafia prosecutor Piero Grasso after consulting in Brindisi with investigators. "May no one touch our kids!" he shouted as he got into a car at the site of the bombing.

Anti-Mafia prosecutor Cataldo Motta, based in the nearby port of Lecce, told reporters there were no claims of responsibility. He added that the bombing didn't appear to be the work of organized crime, since fuel and not dynamite, the Mafia's traditional choice of explosive, was used.

Motta said the "international terrorism" angle was unlikely, but stressed that investigators had not ruled out any hypothesis.

In Brindisi, local civil protection agency official Fabiano Amati said the female student died of her wounds after being taken to a hospital and at least seven other students were hospitalized. Sky TG24TV reported the victim was a 16-year-old girl.

Interior Minister Anna Maria Cancellieri, in charge of domestic security, said investigators at this point "have no elements" to blame the school attack on organized crime.

"It's not the usual [method] for the Mafia," she told Sky in a phone interview. The Sicilian-based Cosa Nostra usually targets specific figures, such as judges, prosecutors, turncoats or rival mobsters in attacks, and not civilian targets such as schools.

Monti's office said that the premier, informed during the night of the blast, has ordered flags flown at half-mast for the next three days. He pledged that the government would work to crack down on crime and to "favour the maximum cohesion of all political and social forces to prevent the return in our country of subversive attacks," a statement said.

National anti-Mafia prosecutor Piero Grasso arrived and surveyed the blast scene without making comments to reporters.

Bomb placed on low wall

Outside the school, textbooks and notebooks, their pages fluttering in the breeze, and a backpack littered the street near where the bomb exploded. At the sound of the blast, students already inside the school ran outside to see what had happened.

Brindisi's mayor, Mimmo Consales, said an anti-Mafia procession was due to pass near the school Saturday evening. But Manganelli noted that many such memorial ceremonies were scheduled to be held on Saturday throughout Italy.

Officials initially said the bomb was in a trash bin outside the school, but later ANSA, reporting from Brindisi, said the device had been placed on a low wall ringing the building. The wall was damaged and charred from the blast. Sky TG24 said the device included three containers of fuel. It was unclear if the blast was triggered by a remote control or by a timer. Public high schools in Italy hold classes on Saturday mornings.

A school official, Valeria Vitale, told Sky that most of the pupils were females. The school specializes in training for jobs in fashion and social services, she said.

The bombing follows a number of attacks against Italian officials and government or public buildings by a group of anarchists, which prompted authorities this week to assign bodyguards to 550 individuals, and deploy 16,000 law enforcement officers nationwide.

Minister Cancellieri indicated that after the school blast, authorities' sense of possible targets had been tested.

"Anything now could be a `sensitive' target," she said, adding that the "economic crisis doesn't help." Austerity measures, spending cuts and new and higher taxes, all part of economist Monti's plan to save Italy from succumbing to the debt crisis roiling Greece, have angered many citizens, and social tensions have ratcheted up.

Brindisi is a lively port town in Puglia, the southeastern "heel" of the Italian boot-shaped peninsula. An organized crime syndicate known as the Sacred United Crown has been traditionally active there, but crackdowns have been widely considered by authorities to have lessened the organization's power.