Mexico City ? A small plane crashed in a wealthy Mexico City neighborhood on Tuesday, killing the nation’s powerful interior secretary and at least seven others, and setting dozens of cars ablaze.

Juan Camilo Mourino, 37, was one of President Felipe Calderon’s closest advisers, but has been embroiled in scandal since taking office in the midst of Mexico’s violent fight against drug cartels. He was in charge of the country’s security.

“With his death, Mexico has lost a great Mexican, intelligent, loyal and committed to his ideals and his country,” Calderon told a news conference. “I ask all Mexicans that they don’t allow any event, no matter how difficult or painful, to weaken them in the pursuit of a better Mexico.”

Presidential spokesman Max Cortazar said Mourino and a group of advisers were returning from an event in the city of San Luis Potosi when the plane went down.

Officials say the crash appeared to be an accident, but Calderon said his administration would await for the results of a full investigation.