Sports gear maker Nike Japan Corp. has lost magnetic tapes containing personal data on its customers in the theft of a truckload of its products in Tokyo in August, police sources said Friday.

The tapes contain the names, addresses and phone numbers of some 445,000 of Nike Japan's customers, the Japan affiliate of Nike Inc. of the United States said. However, Nike's data security procedures should prevent the information from being leaked, they said.

Sagawa Express Co., a shipping company based in Kyoto, reported to police Aug. 20 that one of its large trucks had been stolen from its delivery base in Koto Ward, Tokyo. The tapes packed in cases had been loaded onto the 10-ton truck together with Nike Japan products.

The truck was found Aug. 26 in the city of Inashiki, Ibaraki Prefecture, but its load had been taken, the sources said.