Drug dealers in my neighborhood

This afternoon I was clearing out a box of junk that was on my porch. There was a car parked in front of my house with three occupants and the engine on. I didn't think much of it since I was focused on my little project. But as the time passed, I wondered why they were parked out front with the engine still on. Then I noticed something.

The passenger in the back seat had a bag on his lap with an herb-like substance. I watched him fill up smaller bags with that substance. I watched him take some of that substance and fill up a cigarette paper with it, roll it and light it up. I watched the passenger by the driver get out of the car with a slightly filled plastic bag in his hand and go across the street and around the backside of the building where my landlords and I suspect the drug dealers live. By this point I was inside my apartment watching from the doorway. About 5-10 minutes later, the guy comes out with his bag a little heavier. He gets in the car and the young woman driver (think, blonde) is talking on her phone. I see the front passenger open the bag and take out a smaller bag with white powder in it. Then they drive away. I did manage to write down a partial license plate.

I would say the whole thing took about 20 minutes. At first I didn't know why they were parked. And when I saw the backseat guy with his "herbs" I thought about calling the cops. But I also had a bit of fear and trepidation. They had probably seen me. If I had called the cops, would there be retaliation? This crossed my mind. I just didn't know what to do. I think tomorrow I am going to call the police department to ask them. I know this is a rough neighborhood for Vermont. And I know from my neighbors that there are several drug dealers on this street. It's times like this that make me want to move. I just don't know.