Italian police said on Thursday they were checking all embassies in Rome after two people were injured in separate explosions at the Swiss and Chilean missions in what Rome's mayor called a "wave of terrorism".
There was no immediate claim of responsibility but the incidents bore similarities to an episode in Greece last month in which far-left militants were suspected of sending parcel bombs to foreign governments and embassies in Athens.
"It's a wave of terrorism against the embassies," Rome mayor Gianni Alemanno told reporters.
The Italian news agency ANSA said a suspect package had been found at the Ukrainian mission but the embassy later said no dangerous items had been found after a search of the package.
"We're working with bomb disposal experts to ensure that no packages can be opened by inexperienced people," Rome's chief of police Francesco Tagliente told Reuters.
"We still need to understand the nature of these episodes, all the embassies have been alerted".
Police said the injured Swiss embassy employee had been taken to hospital in central Rome suffering serious wounds to his hands after he opened a package in the mailroom.
Bomb disposal experts searched the Swiss embassy offices, located in a prosperous part of Rome which houses many foreign embassies, but staff remained in the building
following the incident, which occurred at around midday (1100 GMT).
"The ambassador is still on site, the embassy has not been evacuated," Maurizio Mezzavilla, a spokesman for the Carabinieri, Italy's paramilitary police told reporters.
Swiss foreign ministry spokesman Lars Knuchel said that so far no one had claimed responsibility for the act.
"The man is an employee of the embassy, he was injured while he was opening a package received in the mailroom which blew up in his hands," Mezzavilla told reporters.
Heightened security fears
The explosion at the Chilean embassy occurred in the early afternoon, hours after the earlier incident.
The victim there was a mailroom employee who was injured in the hands and face when the packet exploded.
Fire engines were stationed outside the Chilean embassy and fire fighters entered the building.
Italian foreign minister Franco Frattini condemned the incident at the Swiss embassy.
"We express our full solidarity with the Swiss ambassador and with all the personnel of this diplomatic representation, which has been the target of a deplorable act of violence that deserves our strongest condemnation," he said in a statement.
The explosions follow the discovery of a rudimentary device in an empty underground train in Rome on Tuesday. However, police said that it lacked a detonator and tests showed it contained no explosive.
Thursday's explosions occurred at a time of heightened security fears in Europe following a botched attack by a suspected suicide bomber in Sweden this month.
The suspected bomber was killed in Stockholm on Dec. 11. Police believe he was planning to attack a train station or department store at the height of the Christmas shopping season.
An anti government demonstration by students last week descended into some of the worst street violence seen in Rome for many years after what Interior Minister Roberto Maroni said was involvement by militant agitators.
However there was no indication of any link to Thursday's explosions.