A large search and rescue operation was launched last night (31 March) after a red flare was launched, which Jersey Coastguard now thinks was a hoax.
Both RNLI lifeboats, the Jersey Fire and Rescue inshore rescue boat, a French helicopter, and Jersey Police were involved in the operation after the flare was seen south of Green Island at around 10pm.
The crews had to deal with challenging conditions. The wind chill took the temperature down to below zero.
The lifeboats were stood down after 1:30am after it was discovered that the flare was set off from the shore.
Jersey Coastguard has issued a warning on social media following the incident.
"Tasking our brave volunteers to head out to sea in horrendous conditions, such as last night, is never taken lightly.
Whilst it may seem like a bit of fun setting off Flares as a hoax, it should never be underestimated the unnecessary risk to lives it causes."
RNLI Jersey has also warned people to only use flares in an emergency at sea where help is needed or the Coastguard orders it.

Plémont gets a pond!
Temporary fuel duty cut proposition withdrawn
Haut du Mont trial begins
WATCH: Two Supertri champions crowned in Jersey
Jersey RFC open season with defeat
Supertri returns to Jersey for all-star showdown
Women jailed for importing £240,000 of synthetic cannabis in spare tyre
Jersey's first Grief Disco offers new way to remember loved ones