14 Jordanian soldiers were also wounded in the explosion near a camp for Syrian refugees
Six Jordanian guards have been killed and another 14 wounded in a car bomb attack at the Jordan-Syria border.
The attack took place near the Rakban camp for Syrian refugees in a remote area of eastern Jordan around 5.30am local time.
A Jordanian official said the attack was launched from the Syrian side of the border.
The vehicle exploded a few hundred metres from the camp, which is home to more than 50,000 people who have fled the Syrian civil war.
The Jordanian army said several other vehicles used in the attack were destroyed.
Earlier this month five people, including three Jordanian intelligence officers, were killed in an attack on a security office near the capital Amman.
Jordan has kept tight control of its frontier with Syria since the outbreak of war in Syria in 2011.
The Rakban crossing is a military zone far from any inhabited area, and includes a two-mile stretch of embankments built a decade ago to combat smuggling.
The rest of the border is heavily guarded by patrols and drones.
Jordan is an ally of the United States and is participating in the campaign against Islamic State.
The country has received large amounts of foreign aid to help cope with waves of refugees fleeing Syria, but has drawn criticism over conditions in the Rakban camp.
Earlier waves of refugees had an easier time reaching Jordan, with some walking just a few hundred metres to cross into the country. Jordan closed those border crossings in 2013.
The United Nations refugee agency said late last year Jordan should accept more refugees and move them to camps closer to Amman.
But Jordan, which has already accepted more than 600,000 UN-registered refugees, has resisted, arguing that IS militants may have infiltrated the refugees’ ranks.