(Want to get this briefing by email? Here’s the sign-up.)

Good morning.

Here’s what you need to know:

“It was gruesome. It was grisly. It was surreal.”

• Eight people were killed and 11 were injured in what Mayor Bill de Blasio called an “act of terror,” after a man drove a pickup truck down a crowded bike path in Lower Manhattan on Tuesday.

Here’s what we know and don’t know about the attack, the deadliest terrorist event in New York City since Sept. 11, 2001.

The suspect, a 29-year old man from Uzbekistan, was taken into custody after being shot by the police. A bystander’s video appears to show him after the attack. Law enforcement officials found notes that indicated an allegiance to the Islamic State, but they said they were treating the case as one of an “inspired” attacker.