AMMAN, Jordan — The Islamic State has claimed responsibility for a suicide attack that killed seven members of the Jordanian security forces and wounded 13 others on Tuesday at a border crossing with Syria, according to a news agency that frequently serves as a conduit for reports about the militant group.

The Amaq News Agency published a video on Sunday from the Islamic State, also known as ISIS or ISIL, that purports to show a militant fighter blowing up a vehicle filled with explosives near a military checkpoint in Rukban, Jordan.

The agency cited only an unidentified source, but it has proved reliable in the past: It was the first to report that the Islamic State was claiming responsibility for the shootings in San Bernardino, Calif., in December; a deadly rampage at a Baghdad mall in January; and an attack in central Jakarta, Indonesia, the same month.

The Jordanian government responded to the attack last week by sealing its borders with Syria, and aid agencies said that 60,000 refugees living in makeshift camps on the border had received little or no food and water since.