The initial deployment of 12-hundred soldiers in 2010 was supposed to last only a year while the Border Patrol hired and trained staff.
Two law enforcement officers tell The Associated Press the FBI is investigating the possibility that the shooting death of a border patrol agent and the wounding of another was a case of friendly fire.
The Mexican military arrested two suspects in the murder of Border Patrol agent Nicholas Ivie.
Reuters news is reporting that the Mexican Army arrested two people Wednesday morning in Agua Prieta, Sonora. The border town lies about 15 miles southeast of where the murder took place.
An FBI spokeswoman in Phoenix said she cannot confirm the arrests.