Cruz's presidential campaign released a new ad on Friday ripping Trump for his history of embracing eminent domain, the power of the government to force people to sell private property.
In theory, the eminent domain is only supposed to be used for the public good. But conservative critics have long accused government entities of abusing this power.
Indeed, Cruz's ad called eminent domain a "fancy term for politicians seizing private property to enrich the fat cats who bankroll them."
The ad's narrator declared that "Trump colluded with Atlantic City insiders to bulldoze the home of an elderly widow for a limousine parking lot at his casino."
This was a reference to Trump's attempted use of eminent domain in Atlantic City, New Jersey, during the 1990s, when the real-estate mogul was investing in the city's casino empire. The widow in question, Vera Coking, refused to sell her home and successfully fought the state's attempt to seize her land.
Trump, the Republican presidential front-runner, has defended eminent domain as necessary for public projects, including the Keystone XL pipeline that is popular with Republican voters.
"Ted Cruz complains about my views on eminent domain, but without it we wouldn't have roads, highways, airports, schools or even pipelines," Trump wrote Friday on Twitter.
Earlier in the day, Trump also released his first attack ad against Cruz, his top rival in the February 1 Iowa caucus. Trump's commercial ripped Cruz for supposedly supporting "amnesty" for people who immigrated into the US illegally, something Cruz has also accused Trump of supporting.