Washington - More than a dozen US embassies in Europe have received mail containing a white powder, but tests of the substance have been negative, the US State Department said Wednesday.

Deputy spokesman Robert Wood confirmed that 15 embassies have received the powder, which was examined for a variety of hazardous substances. The envelopes were postmarked in the state of Texas.

"There have been some initial tests that have been done, and all of them have proved negative," Wood said, adding the State Department was still awaiting the results of a test on powder mailed to the embassy in The Hague.

Embassies in Belgium, Denmark, Estonia, France, Germany, Hungary, Ireland, Italy, Latvia, Luxembourg, the Netherlands, Norway, Spain, Sweden and Switzerland have all received the powder, Wood said.

Wood did not say what the substance was. The Spanish Interior Ministry said the powder mailed to the embassy in Madrid was flour.

The US government stepped up inspections of post following the spate of mailed anthrax attacks in the United States in 2001 that killed five people. The suspect in the case, Bruce Ivins, took his own life in August just before the federal authorities were about to formally charge him.