China raised the security level for its vessels heading through the Strait of Malacca, a key Asian trade route and major oil choke point.
The transport ministry advised Chinese-flagged ships to take heightened security steps and increased its security warning to level three, according to a copy of a July 2 notice posted on a website affiliated with the ministry. A ministry spokesman confirmed the authenticity of the document but declined to provide further details.
Three is the highest security level in Chinese shipping regulations and is used when an incident is likely or imminent, according to a June transport ministry document. By comparison, authorities issued security level two after recent attacks on tankers in the Strait of Hormuz, according to people familiar with the situation, who asked not to be identified discussing government notification.