A flag bearing a swastika placed on a coffin after a funeral in Italy at which far-right extremists gave Nazi salutes has prompted a wave of condemnation.

Rome’s Catholic archdiocese said in a statement that priests at the parish of St Lucy in central Rome, including the one who conducted the service, had no idea about what would happen outside the church.

Pictures posted online showed the coffin bearing the body of Alessia Augello, a former member of far-right group Forza Nuova, covered by the flag.

The diocese statement called the flag “a horrendous symbol that cannot be reconciled with Christianity” and said the episode was an offensive example of the “ideological exploitation” of a religious service.

Police said the incident was being investigated as a possible hate crime.

Rome’s Jewish community expressed outrage that such events could still happen more than seven decades after the end of the Second World War and the fall of Italy’s fascist dictatorship.

“It is unacceptable that a flag with a swastika can still be shown in public in this day and age, especially in a city that saw the deportation of its Jews by the Nazis and their fascist collaborators,” the statement said.

More than 1,000 of the city’s Jews were deported, most to the Auschwitz death camp in Nazi-occupied Poland, after a raid on the capital’s Jewish neighbourhood on 16 October 1943. Only 16 returned.

The Jewish community statement said the funeral incident on Monday was “even more outrageous because it took place in front of a church”.

A similar episode took place outside another Rome church in March of last year.