News is currently breaking of an attack in Nice, France, where a truck was reportedly driven into a crowd killing dozens.

Here is what has been reported so far:

The incident happened at around 10:30 p.m. local time on Thursday when a truck drove into a crowd at the Promenade des Anglais, where fireworks were taking place. The crash prompted hundreds of people to run from the area in panic, fearing an attack.

Mayor Christian Estrosi said on Twitter that “dozens” of people had been killed, but provided no specific figures. “Dear Nice, the driver of the truck appears to have left dozens of people dead. Stay for the moment inside your home. More information to follow,” he said.

Details about what led to the crash were not immediately available, but local authorities said a terrorist attack appeared likely, prompting the city to warn residents to stay at home. Other details are not yet available.

Bastille Day – formally known as La fête nationale – is celebrated on July 14 and marks France’s National Day.

This post will be updated as more information becomes available.

UPDATE: Police are reporting that approximately 30 people were killed in the attack and as many as 100 have been injured. Apparently police and the driver of the truck exchanged gunfire which appears to have been what finally stopped the driver of the truck. More details to come.

UPDATE: News agencies are now upgrading the possible death toll to “as many as 60.” Witnesses are saying that the driver of the truck appeared to accelerate as he began to hit bodies. Details are still very sketchy at this point and what we know is very grisly indeed. Still no indication of who (if anyone) is claiming responsibility for the attack.

UPDATE: The death toll has now been upgraded to “at least” 73, and the scene in France is unbelievably grisly. Donald Trump has announced that he will be postponing his expected unveiling of Mike Pence as his VP tomorrow.