Police are fine-tuning their raid tactics using a new purpose-built facility - paid for by criminals.
West Midlands Police said there was a "sweet irony" to officers training to force entry to suspects' homes using equipment funded by "ill-gotten gains".
The mock building, at the force's Park Lane base in Aston, Birmingham, replicates the type of property police may face during a raid.
The majority of the project has been paid for using a £30,000 donation from the Proceeds of Crime Act fund, which is made up of money seized from convicted criminals.
Sergeant Dave McGrory said: "Gaining swift access to properties is vital in order to make arrests and seize evidence before suspects can try to dispose of it.
"The new rig will ensure our specialist method of entry officers can refresh their skills and stay at the very top of their game.
"There's a sweet irony that our officers are training to force entry to the homes of crime suspects using equipment funded through the ill-gotten gains of offenders."