Updated

A police officer accidentally shot and killed a soccer fan Sunday while trying to break up a fight by a Tuscan highway between supporters of rival teams, authorities said. Enraged by the killing, hundreds of fans rioted in Rome, attacking a police station.

Fans stormed the yard of a police station near the Rome's Olympic Stadium, hurled stones at passing police cars, and smashed windows at the nearby Italian Olympic Committee headquarters.

Hundreds of youths, many with their faces covered by scarves and ski masks, dragged metal barricades and trash bins to block off one end of a bridge spanning the Tiber near the station. The rioters smashed a window in the police station and set a police vehicle on fire inside the gate.

Sky TG24 TV showed images of flames from what it said was a bus set on fire near the barracks.

Rome's police headquarters said the barracks was under attack but did not give details. It said some arrests were made but did not give a number.

The ANSA news agency reported that at least 10 police suffered injuries near the Rome stadium, but police said there only a few injuries and they were minor.

RAI state TV, reporting from the stadium, said one of its cameramen was injured as well as a cameraman for a private network.

In the Tuscan town of Arezzo, police chief Vincenzo Giacobbe said the fatal shooting of the fan was "a tragic error" that occurred when a police officer intervened in a scuffle between two groups of people.

"I express deep sorrow and sincere condolences to the family of the victim," Giacobbe said.

Gabriele Sandri, a 26-year-old DJ from Rome and a fan of the city's Lazio soccer team, had been traveling to the northern city of Milan for Lazio's game against rival Inter Milan. He was hit in the neck by a bullet while in a car at the rest area along the A1 Autostrada highway near the town of Arezzo, about 125 miles north of Rome.

Arezzo police, reading a statement, said officers in two patrol cars who were stopped on the opposite side of the highway turned on their sirens when they "heard yelling, screaming" and realized the occupants of three cars in the rest area were fighting.

When the clash continued, the police fired warning shots into the air. All three cars began to return the highway, police said, adding that one of the occupants of the vehicles "took a shot." The car with Sandri in it drove a few miles to the next exit to seek medical help. An ambulance crew was unable to revive him, police said.

They described the officer who fired the shots as a veteran but didn't provide the officer's name, and, adding that the case was under investigation, refused to answer questions.

Several Italian TV channels showed Sandri's brother, Cristiano Sandri, gesturing angrily and yelling "they killed my brother." A man described by Sky TG24 as the family's lawyer repeatedly said that the shooting amounted to "first-degree murder."

Clashes between rival fans at rest stops are common in Italy.

Sky quoted witnesses as saying the other two cars were vans carrying Juventus fans from Naples heading to a match in Parma.

The Italian soccer federation postponed the Inter-Lazio game, and security officials in Rome canceled a Sunday night match between Roma and Cagliari. Other games on Sunday started 10 minutes late, with players and referees wearing black armbands.

Premier Romano Prodi, who was attending Mass when he was informed of the death, called fan violence "very worrisome."

The killing also prompted clashes between fans and police in Bergamo, where AC Milan was playing Atalanta. The match was stopped after seven minutes when Atalanta fans tried to break through a barrier and storm onto the field.

Last season, a policeman was killed in riots following a game between Palermo and Catania in Sicily. Under new anti-violence measures this season, some fans have been barred from traveling to games.