From Derbyshire Police:

We now have images of men we would like to speak to about these robberies.

The reference number for this crime is 20000153866.

At around 2.10pm on Thursday 19 March, three teenage boys entered the University of Derby site from Carsington Crescent.
Two youths on bicycles followed them and chased them onto Broadway and Broadway Park Close. They caught up with the boys and threatened them, taking their wallets and some clothing.
The reference number for this crime is 20000153866.
We are linking this crime to another that happened on the same day at about 6pm. A man walked from Willow Row onto Lodge Lane and noticed a youth on the pavement who called him over. Two youths on bikes then approached him and the three robbers surrounded him. They threatened him and took his mobile and Apple air pods.
The reference number for this crime is 20000153915.

If you have information which could help, contact officer in the case PC Matthew Ward via the below methods;
Facebook – send us a private message to /DerbyshireConstabulary
Twitter – direct message our contact centre on @DerPolContact
Website – complete the online contact form www.derbyshire.police.uk/Contact-Us.
Phone – call us on 101.
You can also call Crimestoppers anonymously on 0800 555 111.

Update: Mugging - Broadway