Jordan's King Abdullah has vowed to hit back "with an iron fist" against any group that seeks to harm the country's security or borders.
The palace issued the statement on June 21 after six border guards were killed in a car bomb attack in a desolate area where the borders of Jordan, Syria, and Iraq meet.
The military said 14 other people were wounded when the vehicle exploded a few hundred meters from a camp for Syrian refugees located in a desolate area where the borders of Jordan, Syria, and Iraq meet.
Authorities said several other vehicles involved in the attack were destroyed.
Hours after the attack, Jordan declared the northeastern and northern borders closed military zones.
No group has claimed responsibility, but the Islamic State (IS) group has threatened in the past to "break down" Jordan's borders.
The kingdom is part of the U.S.-led coalition against the IS group and has carried out air strikes on militants in Syria.