Mexico's president, Felipe Calderon, has cancelled plans to attend this weekend's Asia-Pacific summit in Hawaii because of the death of his interior minister in a helicopter crash.
Francisco Blake Mora was one of Mr Calderon's closest allies, and played a leading role in the fight against drugs gangs.
The helicopter was taking the minister and deputy interior secretary Felipe Zamora Castro to a meeting in the state of Morelos when it crashed outside Mexico City. All eight people on board were killed.
Mr Calderon says the weather was probably to blame.
Mr Blake Mora, 45, was appointed to the post last year. The BBC reports he earned a reputation as a hardliner in Mexico's struggle with drug cartels.
One of his predecessors, Juan Camilo Mourino, was killed in a plane crash in Mexico City three years ago.