The incident occurred near the town of Les Sables d'Olonne on 7 June when a seven-strong crew from the French National Society of Sea Rescue (SNSM) was trying to help out another vessel that got caught in storm Miguel, which reportedly brought winds of up to 80 miles per hour. While four of the rescue workers made it to the shore, the other three perished in the storm.
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The people are marching along the coastline, with some of them carrying white flowers in their hands. Rescue workers have also unfolded the flag with the SNSM emblem, the France Info broadcaster reported.
The march is set to end with laying flowers at the site where the capsized boat was washed up, the broadcaster added.