Parts of the Credit Suisse headquarters in New York were evacuated on Wednesday due to a suspicious package that arrived in the mail, police said, a week after a letter bomb was sent to Deutsche Bank in Germany.

A law enforcement source said the package was being treated as a copy of an attempted letter bomb attack on Deutsche Bank headquarters in Frankfurt last week.

We have a report of a suspicious package in the building so we're investigating. We are evacuating at least part of (the building), the New York police said, adding that the bomb squad were at the scene.

In Frankfurt last week, an envelope containing explosives sent to the head of Deutsche Bank, Josef Ackermann, but it was intercepted before it reached him.

An Italian anarchist group has claimed responsibility for sending the letter bomb to Ackermann and may have sent two more packages, German investigators have said.

A hidden, rolled-up letter written in Italian from the Federazione Anarchica Informale (the Informal Anarchist Group, or FAI) spoke of three explosions against bankers, banks, fleas and bloodsuckers, the German investigators said.

The FAI previously claimed responsibility for a parcel bomb that injured two people in the offices of the Swiss nuclear lobby group in March, as well as for parcel bombs sent last year to the Swiss and Chilean embassies in Rome.

A United States official told Reuters last week that FBI agents in Germany were in touch with German authorities about the investigation, but that the FBI was not aware of any specific or related threat to New York.

(Reporting by Michelle Nichols and Mark Hosenball, editing by Philip Barbara)