"Quick, find the yellow brick and break a window."

I found the following post on a website I visit from time to time. I love the logic behind it and concern for the budget of their city. But I question how often they need such a brick.  Any guesses what the brick says or the sign on the wall?


  

In the Chinese province of Heilongjiang, the Public Transport Company replaced the emergency-use hammers with pairs of yellow bricks on all city buses.

“The special hammers are expensive and people were always stealing them,” explained a spokesperson from the Harbin Public Transport Company. “We don’t think anybody will be interested in stealing bricks.”