ROME - A man opened fire on passersby in the central Italian city of Macerata on Saturday, injuring several African migrants, police said, in an attack that appeared to be racially motivated.

The shootings happened just days after the dismembered body of an 18-year-old Italian woman was discovered hidden in two suitcases near Macerata. A 29-year-old Nigerian migrant has been arrested in connection with her death.

Local media reported that at least six migrants including one woman were shot by a man driving around the city, located about 200 km (125 miles) east of Rome, and firing from his car window.

"Shots fired in Macerata. People injured. Police operation under way. Stay out of the way and avoid open places," the police said on Twitter. Shortly afterwards, police said one man had been arrested.

State television Rai said the suspect was a white Italian man who came from Macerata.

The website of newspaper Corriere della Sera said a man fired from a car window at two young African migrants shortly after 11 am (1000 GMT) Saturday, wounding one of them. A short while later two other migrants, including a woman, were shot.

It was not immediately clear how serious their injuries were.

Right-wing politicians campaigning ahead of national elections on March 4 leapt on the gruesome death of the teenager Pamela Mastropietro to promote their anti-migrant message.

A preliminary postmortem on the teenager could not immediately identify her cause of death. The Nigerian suspect, who was denied asylum last year but has remained in Italy, has refused to talk to police.

"What was this worm still doing in Italy?" Matteo Salvini, head of the far-right League, wrote on Facebook, accusing the center-left government of responsibility for Mastropietro's death for allowing migrants to stay in the country.

"The left has blood on its hands," he wrote.

Magistrates say witnesses saw the Nigerian suspect carrying the suitcases that were later found to contain the teenager's body. They also found blood-stained clothes and knives in his possession.