Mexico City - Mexican Interior Minister Juan Camilo Mourino and a presidential adviser on security issues died when a small plane crashed in the Mexican capital, Mexico City Mayor Marcelo Ebrard said.

The crash left eight people dead and at least 40 injured, Ebrard said. However, he noted that the authorities could not immediately confirm whether all eight of the dead had been travelling on board the plane.

President Felipe Calderon expressed "enormous sorrow" over the death of his interior minister and close friend.

With his voice breaking, Calderon recalled that Mourino had been his companion in politics for several years and that they dreamed together of "a new homeland."

Mourino, 37, regarded as Calderon's right-hand man, and Jose Luis Santiago Vasconcelos, a former deputy attorney general and a current adviser to the government, were returning to the capital from San Luis Potosi on the aircraft that crashed.

It crashed in a luxury office area in western Mexico City.

Ebrard said 40 people who were on the ground were injured, at least five of them seriously, while more than 1,000 people were evacuated from the area because the crash caused a fire. He noted that 30 vehicles were damaged as a result of the accident - 10 of them were charred.

The mayor said the plane apparently tried to make an emergency landing on the street where it crashed.

Calderon praised Mourino's ability to negotiate and his dedication to work in a short speech at the Mexico City airport after the president returned to the capital earlier than planned from a trip to the western city of Guadalajara.

The president said he would decide within a few hours who was to succeed Mourino as interior minister.

Ebrard, who arrived at the site of the accident shortly after it happened, said two pilots and at least four other people were travelling on board the plane - a Lear Jet 45 belonging to the Mexican government.

Mourino coordinated Calderon's presidential campaign and headed the president's office before becoming interior minister in January.

Mexico's interior minister is in charge of the country when the president is abroad, and he is in charge of relations with the legislature and state governors.

The accident caused a commotion in Mexico, and both the Attorney General's Office and civil aviation authorities were investigating the crash.

Mourino's death reminded Mexicans of the death of Ramon Martin Huerta, public security minister under president Vicente Fox (2000-2006), who died in 2005 in a helicopter accident that was blamed on human error. (dpa)