Package bombs exploded at the Swiss and Chilean embassies in Rome on Thursday, wounding the two people who opened them, officials said, in attacks that bore similarities to bombings in Greece last month.
No group claimed responsibility, but Italian Interior Minister Roberto Maroni said anarchists were thought to be behind the blasts in Rome.
"Various elements lead us to believe that this is the correct path," he was quoted as saying by the ANSA news agency.
On Nov. 2, suspected Greek radical anarchists sent 14 mail bombs to foreign embassies in Athens, French President Nicolas Sarkozy, German Chancellor Angela Merkel and Italian Premier Silvio Berlusconi. Two of the devices exploded, causing no injuries.
A group called Conspiracy Nuclei of Fire claimed responsibility for the Greek blasts. It called on militants in Greece and other countries to step up their action, and Greek police noted Thursday that in the past, acts of "solidarity" have been carried out between Greek and Italian militant groups.
All embassies in Rome were informed of the blasts and Italian diplomats abroad were urged to take precautions.
The first bomb exploded inside the Swiss Embassy at around noon (1100 GMT, 6 a.m. EST). The man who opened it was hospitalized with serious hand injuries, but his life was not in danger, Swiss ambassador Bernardino Regazzoni said.
He recalled that the Swiss Embassy in Athens had been a target of the November letter bomb campaign and that a device had been found outside the grounds of the Rome Embassy in early October.
At the time, he noted, some had speculated that an anarchist-ecological group might have been responsible.
About three hours after the Swiss Embassy blast, a small parcel bomb exploded inside the mailroom of the Chilean Embassy, slightly wounding an administrative official, Chilean Foreign Minister Alfredo Moreno said in Santiago. The official went on his own to the hospital for treatment.
Chilean Ambassador Oscar Godoy said the parcel - smaller than a package but bigger than a letter - had been addressed to the Chilean cultural attache. He called it "an unexplainable act of terrorism, irrational and brutal."
Rome police chief Francesco Tagliente said a suspicious package that drew police to the Ukrainian Embassy was a false alarm.
The Swiss Embassy beefed up its security after consulting with Italian authorities and that security at all foreign missions would be reviewed, Swiss Foreign Minister Micheline Calmy-Rey said. Possible extra measures, she added, could include additional protective walls or fences, surveillance cameras and evacuation plans.
There have been growing concerns in Europe about holiday season attacks following a suicide bombing in Sweden and security services' fears of an assault on a European city modeled on the deadly shooting spree in Mumbai, India.
On Tuesday, there was a bomb scare in Rome's subway system after authorities discovered a suspicious package with wires and powder under a seat. The device ended up being a fake, with police determining there was no trigger mechanism and its the powder was inert, cement-like material.