Car park accident with a parked car?

I had a minor accident on a supermarket car park yesterday. Pulling into a bay I touched my car’s bumper with that of another car. There was no-one in the car so I assume they were still shopping.

Realizing the space might be a little narrow, I decided to park in the next row, where I had a look at the little scratch on my bumper and hunted for paper and a pen. I then wrote down my name and phone number and went to put the paper under the other car’s wiper, however being absorbed in what I was doing I didn’t the vehicle leave.

I then went inside the store to ask if they had CCTV coverage of the car park to try to find the car’s registration number to try to contact them so I could apologize and sort it out properly. It seems the store has very limited CCTV so unless it occurred right outside the doors the incident was not seen.

I asked with customer services and security whether there had been any report of damage to a car, but the owner seems not to have noticed and driven off. I then gave my name and phone details to customer services, along with the best description I could give of the car, in case the owner came back. I have so far heard noting and it has been around 14 hours.

I am aware that the police should be informed of incidents within 24 hours, however I am unsure what information I could give them. The car was fairly new, grey and a small 4×4 but I don’t have any more information then that.

The security person at the supermarket told me to leave it because accidents happen all the time on the car park. But I am very aware it could be very serious if there was a witness, plus I feel very guilty.

Do I go to the police with the little information I have? If so, what do they do? Do they track down all grey 4x4s in the area and ask if they have a scratch or just see if someone makes a claim that matches my description?

I was initially hoping this could be settled without going through insurance but I assume this isn’t an option if the police get involved?

Any information or advice would be greatly appreciated.