Germany wants the European Union to introduce new security measures against militant attacks via air freight to help improve a patchwork of different rules around the world, officials said.

A German government source said EU interior ministers would discuss next week how to respond to two spates of parcel bombs in the past week -- sent from Yemen to U.S. targets and by bombers in Greece to embassies and European governments.

The bombs from Yemen have been blamed on al Qaeda, while those originating in Greece have been blamed on leftists. "The EU summit in mid-December should then decide on proposals for a package of EU-wide measures," said the source.

One of the Greek bombs was addressed to German Chancellor Angela Merkel and reached her office in Berlin by air cargo. She was out of the country at the time and the bomb was deactivated before it could do any harm.

Merkel urged better international coordination of security rules for air cargo, telling a Bavarian newspaper: "We have a global patchwork of security rules for air freight."

She said the German government was working hard to protect its people, but added: "I don't want to sugar coat it, though -- the danger exists. Everyone must be on the alert."

Bombers in Greece posted explosive-packed parcels to a number of embassies in Athens and to several European governments.

About security of courier packages and Merkel's proposals, Greek Foreign Minister Dimitris Droutsas said:

"The security of such courier services ... is a general problem that must be addressed. I can imagine that there will now be a discussion about this issue on a European but also necessarily international level."

LEFTIST GUERRILLAS
Greek police blamed the bombs on leftist guerrillas. The Greek left is angry about an austerity plan imposed on Greece in exchange for an EU bailout.

Germany was the biggest contributor to the Greek rescue package after Merkel insisted on deep Greek budget cuts.

The Greek bombs were discovered just days after explosives were found in Dubai and Britain packed into computer printer cartridges addressed to synagogues in Chicago. The bomb found in Britain had passed through Germany en route.

Last month the United States and Britain advised caution to travellers visiting Germany and France. Germany's police chief said the parcel bombs gave Germany "cause for concern and caution -- though not panic".

"The situation in Germany is still that there is a high level of non-specific threat, there are lots of rumblings that force us to remain on a high level of alert," Federal police chief Joerg Ziercke told Bild newspaper. (Reuters)