New Zealand's two main tobacco companies halted sales of loose tobacco today after suspicious white powder was found in a packet.
A series of letters, some containing traces of cyanide, have contained threats to poison food and drink in New Zealand and target the interests of Britain, Australia and the United States.
One letter, sent before Iraq war broke out, threatened action if events escalated in that country.
A white substance was found in a tobacco pouch bought at a supermarket in the North Island city of Tauranga, prompting fresh calls from police for the public to report any broken seals on food and drink.
"In the interests of public safety and as a precautionary move British American Tobacco [BAT] and Imperial Tobacco have issued an immediate product freeze on the sale of all roll-your-own tobacco," BAT said.
The two British rivals, which between them control most of the New Zealand tobacco market, said the freeze would apply until the results were known of police analysis of the powder, probably tomorrow.
The New Zealand Heraldnewspaper said this month it had passed to police a letter that threatened to poison water supplies, use explosives, gas a cinema and attack the interests of Britain, Australia and the United States in New Zealand.
Police said there were similarities between the letters and one sent in 2001 to the US Embassy in Wellington, which contained cyanide and a threat to disrupt the 2002 NZ Golf Open, attended by Tiger Woods. That threat also came to nothing.
Cyanide is widely used by New Zealand farmers and local government agencies to kill animal pests such as possums.