BERLIN, Aug 30 (Reuters) - German authorities have

warned businesses that packages containing incendiary devices

had caught fire en route across Europe and that more such

parcels could be circulating, a letter to companies seen by

Reuters showed on Friday.

A spokesperson for the federal criminal police known as BKA

said the letter had been sent to German companies and business

associations, declining to provide further details.

In the letter dated Wednesday, BKA and Germany's domestic

intelligence service said they had received information on

"several consignments dispatched by private individuals in

Europe that caught fire on their itineraries in several European

countries".

The packages contained electronic consumer devices and

containers with liquids and were likely prepared with the

intention to damage logistics infrastructure, according to the

letter. It could not be ruled out that more "unconventional

incendiary devices" will be circulating, it added.

However it did not say if there was any indication of who

had sent the packages, or where the fires had happened. The

letter and the BKA spokesperson did not specify any damage

caused by fires so far.

Shipping business DHL said two cases had affected

its Express parcel delivery network.

"DHL Express has taken measures in all European countries to

protect its network, its staff and facilities as well as

customers' consignments," DHL said.

Airline Lufthansa's air freight unit Lufthansa

Cargo said it had not been affected but was in touch with the

authorities.

German news agency dpa first reported on the letter, saying

it was sent specifically to logistics and freight companies.