The Missouri House is asking the U.S. Justice Department to investigate the high price of propane.
The resolution endorsed Thursday was adopted by a voice vote and now heads to the Senate where a similar measure was also passed this week.
Lawmakers began considering the measures after propane prices jumped over $5 per gallon in January. Propane associations say the high prices are caused by colder weather and higher-than-expected crop yields.
But Missouri legislators have accused the industry of price gouging by boosting exports and causing a shortage back home.
Missouri Attorney General Chris Koster is also investigating. Gov. Jay Nixon has announced an additional $15 million in aid for low-income propane customers to cope with the high prices.