Investors and traders are monitoring how Iran will respond after Israel attacked nuclear and military targets across the Persian Gulf country on Friday. 

While most attention has focused on whether Tehran might try to close the Strait of Hormuz chokepoint — through which a swath of the world’s oil flows — the notice serves as a reminder of the potential for wider disruption to merchant trade.

“Marine operators have reported significant electronic interference in the region,” a notice from the Joint Maritime Information Center said. 

It advised companies to “closely monitor all electronic aids and communication networks for electronic interference. Be ready with alternative options should navigation aids fail.”

False location signals and jamming of vessels’ navigational equipment have become a growing feature of the commercial shipping industry in the past few years. Russia’s war in Ukraine and Houthi attacks on ships have both contributed to strange and erroneous vessel signals.

The JMIC comes under the Combined Maritime Forces, a 46-nation coalition of navies led by the US in Bahrain, that seeks to ensure safe shipping across the region.