It is believed that the lanterns, released on Tuesday evening, were also spotted by a person in Cancale, a small town east of St Malo, who called the Joburg Coastguard after mistaking them for red flares.
Ports of Jersey said that sky lanterns could be dangerous, as they could travel large distances and float high enough to interfere with plane engines, depending on the wind. If they land on the ground still lit, they can cause fires.
A Ports of Jersey spokesman said: ‘We are reiterating the rules around releasing lanterns.
‘They can be dangerous to planes and they can also be misinterpreted as flares, as they seem to have been in this particular case, which can cause the Coastguard to launch the lifeboat.’
