A second major power outage in as many days has struck France’s Riviera region, as a fire broke out overnight at an electrical substation in Nice. Authorities suspect the incident was a deliberate act of sabotage.

The blaze, which ignited around 2:00 a.m. local time on Sunday, left approximately 45,000 homes without electricity. The outage affected not only the city of Nice but also disrupted operations at Nice Airport, the city’s tramway system, and the nearby towns of Saint-Laurent-du-Var and Cagnes-sur-Mer. Power was restored later that morning.

Local police reported signs of forced entry at the substation, including tyre marks and a broken door—indicators pointing to possible criminal activity. Nice's deputy mayor, Gaël Nofri, stated the fire was "probably of criminal origin."

The incident follows a similar event in Cannes just a day earlier, where a suspected arson attack on a substation during the ongoing international film festival led to a massive blackout. About 160,000 homes were affected, and film screenings were temporarily halted until private generators were deployed.

Although both incidents appear to involve sabotage, no direct connection has yet been confirmed.

Nice Mayor Christian Estrosi condemned what he called "malicious acts that affect our country" and announced plans to bolster security around the city’s energy infrastructure.

Prosecutors have launched an investigation into suspected "organised arson." Nice’s chief prosecutor, Damien Martinelli, confirmed that authorities are working to determine the cause and method of the attack.

As the probe continues, officials are treating the incidents with heightened concern amid fears of further disruptions to the region’s power grid.