Under the direction of CEO Aubrey McClendon, Chesapeake Energy Corp. plotted with its top competitor to suppress land prices in one of America's most promising oil and gas plays, a Reuters investigation has found.

In emails between Chesapeake and Encana Corp, Canada's largest natural gas company, the rivals repeatedly discussed how to avoid bidding against each other in a public land auction in Michigan two years ago and in at least nine prospective deals with private land owners here.

In one email, dated June 16, 2010, McClendon told a Chesapeake deputy that it was time "to smoke a peace pipe" with Encana "if we are bidding each other up." The Chesapeake vice president responded that he had contacted Encana "to discuss how they want to handle the entities we are both working to avoid us bidding each other up in the interim." McClendon replied: "Thanks."