SUVA (AFP) - The United States Embassy in Fiji was placed under tight security Wednesday after receiving a suspicious package containing white powder, police told local media. All access routes to the embassy were closed in the clampdown, Radio Fiji reported. At least 18 other US embassies around the world have received white powder this month, as well as more than 40 governors' offices in the United States. Initial tests showed the substance was harmless but the deliveries sparked security alerts. Fiji police spokeswoman Ema Mua said they were treating the situation as "high alert" and the powder had been taken away for analysis.