On April 16th Jordan, for the first time since the Syrian rebellion began in 2011, ordered its warplanes to attack vehicles trying to sneak into Jordan. In this incident a convoy of three camouflaged trucks was spotted crossing in a rural and thinly populated area and despite threatening moves from aircraft and warning shots refused to halt. So the warplanes were ordered to attack and destroy them. Jordan released aerial photos of the burning wreckage, but not anything on casualties. It is believed that most of the men in the trucks fled on foot once they saw the aircraft coming low to attack.
The crossing was also near the Iraq border and some speculate that the vehicles were carrying al Qaeda men from Iraq who chose to sneak in via the less well guarded Syrian border and were possibly headed for a nearby American run training camp (for Syrian rebels). Jordan is also threatened by increased Islamic terrorist activity within its borders, often assisted by Islamic terror groups operating in Syria. So Jordan is asking Western and Arab nations for more help, or risk having another humanitarian disaster to deal with. For over a year now Jordanian police have been arresting Syrians trying to smuggle weapons into Jordan. Some shipments contain anti-tank missiles and surface-to-air missiles. This stuff is believed to be for Islamic radicals in Jordan who want to overthrow the monarchy (as they have been doing for decades). Jordan has allowed U.S. and Arab Gulf State weapons to be smuggled from Jordan into Syria and fears that some of these weapons are ending up with Islamic radical rebel groups that sell some of them to Islamic radicals inside Jordan.
Jordan is also angering Islamic terrorist groups by operating refugee camps for Syrians and not tolerating any misbehavior. For example, on April 6th a riot by Syrians in a Jordanian refugee camps turned violent and at least one refugee was killed. The unrest was all about the higher level of policing found in Jordan and in this case the police arresting a man for trying to smuggle a family out of the camp. Jordan does not want a lot of refugees living outside the camps, where they become a source of trouble for Jordanians and often get involved in criminal activities. The police also crack down on criminal activity inside the camps. The Syrian refugees resist the sort of control and so far the Jordanian police are winning. Jordan has some of the most professional and efficient police and military personnel in the region. Thus the use of the Jordanian Air Force against armed groups trying to sneak into Jordan is partly a warning that Jordan remains a very inhospitable place for Islamic terrorists.