A man lost six members of his family in the horrific lorry massacre in Nice, French media reported.
The man, named as Christophe Lyon, was with his wife, her 28-year-old son, his parents and his parents-in-law when they were killed in the Promenade des Anglais attack, the Republicain Lorrain newspaper said.
The sole survivor was said to be too traumatised to speak.
Francois Locatelli, 82, and Christiane Locatelli, 78, their daughter, Veronique Lyon, 55, and Michael Pellegrini, 28, their grandson, had gone for a brief holiday to the French Riviera.
They met up with Veronique's in-laws - Gisele Lyon, 63, and Germain Lyon, 68, who were also killed. Their son, Christophe, was the sole survivor.
The Locatellis were well-known in the township of Longwy in north-eastern France, where Francois had worked as a heating engineer and his grandson taught economics and social studies.
At least 84 people, including around a dozen children, died when a terrorist drove a truck through crowds celebrating Bastille Day.