At least four civilians, two Malian police officers and a customs officer were reportedly killed in an attack on a border post on Mali’s boundary with Burkina Faso, security sources and government officials said Monday, May 20.

“Armed men attacked the border post at Koury on Sunday night,” said a local police officer, who wished anonimity. “Two gendarmes, a customs officer and four civilians, including two Ghanaians, were killed.”

Koury, in Mali’s southern Sikasso region, lies about 480 km (300 miles) east of the capital Bamako near the border with Burkina Faso and is a major crossing point for goods entering or leaving Mali.

Another security source confirmed the toll and said the two Ghanaians were lorry drivers.

“The assailants arrived on three motorbikes and in a car,” the source said. “They fired at the gendarmes, the customs officers and the civilian truck drivers.”

“Right now, we can’t confirm who the attackers were. They arrived in Koury from two directions,” a government official said. “We were told that they took the soldiers’ boots as they left.”

The attack comes a day after a United Nations peacekeeper was killed and another injured in a roadside bomb attack in Timbuktu in central Mali.

In March, French and Malian troops launched a major counter-terror operation in the Gourma region near the Mali-Burkina Faso border.