A gunman who shot and seriously injured two policemen outside the Italian PM's office in Rome was acting out of anger at politicians, prosecutors allege.
A suspect named as 49-year-old Luigi Preiti was arrested at the scene.
Rome prosecutor, Pierfilippo Laviani, said the gunman had hoped to target politicians but as he was unable to, he shot the police officers instead.
The attack came as a new government was sworn in across the city at the Quirinale Palace.
Democratic Party Deputy Leader (PD), Enrico Letta, 46, becomes prime minister at the head of a "grand coalition" including Silvio Berlusconi's People of Freedom party (PDL).
Mr Preiti was reported to be an unemployed man from the southern region of Calabria with no criminal record.
The Ansa news agency said the gunman, dressed in a dark business suit, fired several shots outside the Chigi palace, about a kilometre (mile) away from the Quirinale and had acted alone.
There had been earlier reports that the gunman may have suffered mental problems.
Ansa quoted Mr Preiti's brother as saying that Mr Preiti suffered no such disorders and that the family was shocked at what had happened.
The agency reported that Mr Preiti had separated from his wife, with whom he has a son.
Prosecutor Pierfilippo Laviani said Mr Preiti had "lost his job, he had lost everything".
"He has confessed everything. He doesn't seem to be a deranged individual," Mr Laviani said.
The new Interior Minister Angelino Alfano said it appeared the shooting was an "isolated act" and that there were no concerns for "the general situation of public order in the country".
The most seriously hurt police officer was named as Giuseppe Giangrande, who suffered neck or spinal injuries and is being treated at the Policlinico Umberto.
The second officer was also seriously hurt, with a leg wound, while a pregnant woman who was passing by was slightly injured.
Mr Preiti was being treated at a separate hospital.
Rome Mayor Gianni Alemanno said shortly after the shooting: "It's not an act of terrorism but certainly the [political] climate of the past few months has not helped."
Italy had been in political deadlock since February's general election. A new government was agreed on Saturday.
Correspondents say the new "grand coalition" between Italy's current main right- and left-wing parties is unprecedented, and will probably prove an uneasy alliance.
Mr Berlusconi will not be a minister but Mr Alfano, the PDL secretary and one of Mr Berlusconi's closest political allies, is the deputy PM as well as interior minister.
Bank of Italy director general Fabrizio Saccomanni heads the powerful economy ministry and Emma Bonino is foreign minister.
The third strongest force to emerge from the Italian election, the Five Star movement led by former comedian, Beppe Grillo, has refused to take part in a coalition.
The country is still plagued by economic woes after becoming one of the first eurozone victims of the global financial crisis of 2008.