The British authorities have warned the shipping industry of two alleged pirate groups operating in the Indian Ocean.
The first group is operating about 600 nautical miles south of Socotra in Yemen, and the second is operating a few hundred nautical miles to the east of the first, the UK Maritime Trade Operations agency said in a social media post on Tuesday.
"Both pirate action groups could include a mothership and a number of small crafts," the agency said.
"Vessels are advised to transit with caution and report any suspicious activity to UKMTO."
Several suspicious approaches by small craft towards cargo ships have been reported over the past week. It is unclear whether the activity is related to the war in Gaza, like the Houthi attacks off the coast of Yemen, or more conventional piracy.