What happens to Christopher at the police station?

From the text:

When I got to the police station they made me take the laces out of my shoes and empty my pockets at the front desk in case I had anything in them that I could use to kill myself or escape or attack a policeman with.
The sergeant behind the desk had very hairy hands and he had bitten his nails so much that they had bled. This is what I had in my pockets:
1. A Swiss Army knife with 15 attachments including a wire stripper and a saw
and a toothpick and tweezers
2. A piece of string
3. A piece of a wooden puzzle which looked like this

4. 3 pellets of rat food for Toby, my rat
5. £1.47 (this was made up of a £1 coin, a 20p coin, two 10p coins, a 5p coin and a
2p coin)
6. A red paper clip
7. A key for the front door
I was also wearing my watch and they wanted me to leave this at the desk as well but I said that I needed to keep my watch on because I needed to know exactly what time it was. And when they tried to take it off me I screamed, so they let me keep it on. They asked me if I had any family. I said I did. They asked me who my family was. I said it was Father, but Mother was dead. And I said it was also Uncle Terry, but he was in Sunderland and he was Father’s brother, and it was my grandparents, too, but three of them were dead and Grandma Burton was in a home because she had senile dementia and thought that I was someone on television.
Then they asked me for Father’s phone number. I told them that he had two numbers, one for at home and one which was a mobile phone, and I said both of them.
It was nice in the police cell. It was almost a perfect cube, 2 meters long by 2 meters wide by 2 meters high. It contained approximately 8 cubic meters of air. It had a small window with bars and, on the opposite side, a metal door with a long, thin hatch near the floor for sliding trays of food into the cell and a sliding hatch higher up so that policemen could look in and check that prisoners hadn’t escaped or committed suicide. There was also a padded bench.