Both cars were ransacked, before the thief fled. Investigations have been launched into the robbery.
This comes two weeks after a string of car break-ins were reported in Belval and Bonnevoie.
On Monday night, a police patrol in the Gare district noticed the suspicious and nervous behaviour of a man who attempted to flee from the officers.
Suspecting a drug dealer, offices stopped the man for a search. Three balls of heroin as well as a mobile phone and cash were seized from him.
The alleged dealer was arrested on orders of the public prosecutor’s office.
