Jordan is a close ally of the US in the war against terror.

Three US military trainers were shot dead and a third injured on Friday in an exchange of fire with the security guards after their vehicle failed to comply with the orders of the gate guards to stop. They tried to enter the King Faisal Airbase, southeast of the Jordanian capital, Amman, a Jordanian military source said.
 
“There was an exchange of fire at the entrance of the base after an attempt by the trainers' vehicle to enter the gate without heeding orders of the guards to stop,” a statement by the Jordanian Armed Forces said in the aftermath of the incident. The statement stopped short of elaborating on the circumstances of the shooting.
Initial reports were that one was killed, two injured. The two injured service members were transported to a hospital in Amman, where they died. A Jordanian officer was also injured from a bullet in the neck in the incident. 
Sources told Arab News that the Jordanian soldier who was injured in the shooting was not the same soldier who shot-dead the three US troops. However, the shooter was also on duty at the base gate when the incident took place.
A Jordanian official who spoke to Arab News on condition of anonymity because of the sensitivity of the matter, refused to comment if there was any suspicion of terrorism behind the incident. However, he said an investigation has been launched into the shooting to identify reasons and causes behind it.
A US defense official described the incident as “green on blue,” a military term for when friendly forces attack US personnel. “But we can’t say for the moment if it was a deliberate” act to kill US personnel or “some kind of misunderstanding,” the official told AFP.
 “The service members were in vehicles approaching the gate of a Jordanian military training facility, where they came under small arms fire,” the official added. “We are working with the Jordanian government to gather additional details about what happened.”
Later in the day, Jordan Army issued a gag order preventing the media form publishing any information revealing the identities of the victims of the incident.
The airbase is located nearly 300 km from Amman and nearly 150 km from the Saudi borders.
The airbase has long been used for joint military exercises between Jordan and its various allies, including the US, the UK, Saudi Arabia and Egypt. The base is also part of the network in Jordan to train Western-backed Syrian fighters.
Jordanian officials previously said that there are more than 1,000 US military personnel in Jordan, the majority serving as advisers to Jordan’s armed force and Syrian opposition fighters.
Late in 2015, a Jordanian policeman shot dead two US instructors, a South African and two Jordanians at a police training center, east of Amman, before being gunned down.
Washington said at the time that the two Americans killed in that attack were employees of the private firm DynCorp, contracted by the State Department to train Palestinian forces.
DynCorp. International spokeswoman Mary Lawrence said the firm’s employees had all been accounted for after Friday’s shooting and none had been wounded.

Source: Arab News