It's not exactly paranormal but just very strange.

It took place on a weekday morning, in the late 2000s, I dropped my ex at her workplace, and then I start driving towards my own workplace. I need to take a tunnel downtown, there's a traffic light just before the tunnel. The light is red, I wait. The light turns green, I go ahead, along with another car next to me.

Right behind me, in my mirror, I see police cars blocking the street at the traffic light. I'm the last car that went through the traffic light. No other cars can make it behind me.

I'm kinda freaking out. Why are the police cars blocking the way to the tunnel?

I then realize there are only two cars in the tunnel, mine, and the car just before me. No other car. At 9am. On a weekday. What the hell is going on?

I keep on driving, everything seems normal, apart from the complete lack of cars.

Eventually, I see the end of the tunnel, with police cars on either side of the road. And police officers making OBVIOUS signs with their arms : "Get the fuck out of there, quick, faster!".

Me and the other car make it out of the tunnel, then In my mirror, again, I see 4 police cars blocking the way out of the tunnel.

I turned on the radio. Nothing about this event. I searched the news websites for the whole day, I didn't find anything. I asked around, at work, in social media, nobody knew about this. I didn't think of calling the police station. I never learned what the hell happened in this tunnel.

My bet is it was either a bomb threat, or they had to catch a known criminal in this tunnel, or maybe a collapse danger of some kind. But the fact that it didn't make local news is mind boggling to me. I sometimes wonder if I dreamed this.