An Afghan policeman stands at the site of a suicide attack in Kabul ON July 2, 2013. Taliban insurgents, including a suicide bomber in a truck, killed six people in the attack on a foreign logistics and supply company in Kabul on Tuesday. (MOHAMMAD ISMAIL/REUTERS)

Taliban insurgents killed seven people, including four Nepalese guards, in an attack Tuesday on a logistical company that supplies NATO and U.S. forces in the Afghan capital.

The attack was the fourth of its kind in Kabul since June, part of a wave of increasing violence in Afghanistan, which most foreign combat troops are set to leave by the end of next year.

In the pre-dawn strike Tuesday, a suicide bomber blew up a small, explosives-laden truck at the gate of the company facility, police said, leaving a huge crater in the road.

The explosion was followed by an exchange of gunfire with security forces that killed the four Nepalese and one Afghan guard, as well as two civilians, police said.

The attack was the second by the Taliban since the opening last month of the militant group’s political office in Qatar, which American officials have described as the first step toward peace talks to end the U.S.-led war in Afghanistan.

In the most brazen of the attacks, Taliban insurgents wearing foreign military uniforms staged an assault on the presidential palace compound last week. All the militants were killed in the attack, the Taliban said in a statement, some when they detonated explosives and others in a gun battle with security forces. Three Afghan guards also were killed in the commando-style strike.

The spread of violence across the country has led to a rising death toll among civilians and the poorly equipped Afghan security forces. According to Afghan officials, 299 police officers and at least 144 soldiers were killed last month alone.