Police seal off area near government buildings.

A suspicious package which triggered a bomb alert near Italy's government buildings in the centre of Rome turned out to be part of a treasure hunt game organised for tourists.

The area around Palazzo Chigi was cordoned off on Thursday after a woman was observed leaving a metal box behind a fire hydrant on Via dei Sabini before walking away. 

The surrounding streets were swiftly sealed off and those in the vicinity were evacuated as the bomb squad rushed to the scene.

The package was found across the street from where a press conference was scheduled with several senior government figures including Italy's deputy premier and foreign affairs minister Antonio Tajani.

However when the bomb disposal experts analysed the contents of the box they declared it to be a false alarm and the streets were subsequently reopened.

Inside the box they found a packet of sweets wrapped in duct tape along with a piece of paper containing messages in French, some numbers and a drawing of a kitten, reports news outlet RomaToday.

The contents of the package were reportedly clues in a treasure hunt for tourists that had begun earlier that day at the Trevi Fountain, according to Italian newspaper Corriere della Sera.

The incident occurred amid heightened security in Rome due to protests linked to the jailed anarchist Alfredo Cospito and Italy's 41 bis prison regime.

In June 1993, during the Mafia's car bombing campaign, a Fiat 500 packed with explosives was found on Via dei Sabini, reports state broadcaster Rai News.

Photo ANSA