Photo: AP

A week after the Taliban announced its annual spring offensive, armed militants launched an assault, involving a suicide car bombing and a gun attack, against a government security agency in Kabul. At least 28 people have been killed and more than 320 wounded, NPR reports, the Taliban claimed responsibility.

On its Pashto-language website, the Taliban said that it had targeted “Department 10,” a unit of the National Directorate of Security, which protects government ministers and VIPs. From Reuters:

They said a suicide car bomber blew up the main gate at the front of the office, allowing other fighters, including more suicide bombers, to enter the heavily guarded compound.

Taliban spokesman Zabihullah Mujahid said in a separate statement that the attackers were engaged in a gunbattle with Afghan security forces inside the building.

It was not immediately possible to verify the details of the Taliban’s claim with government officials. The Islamist group often exaggerates details of attacks against government and military targets.

The militants struck around 9 o’clock in the morning, NPR’s Philip Reeves reports, in the midst of rush hour. The initial blast could be heard around the city. “It was followed by the sound of a prolonged gun fight. Ambulance sirens intermittently echoed through the streets for hours afterwards,” Reeves said.

Photo: AP

According to the Wall Street Journal, this is the deadliest attack in Kabul since August, when three separate bombings left more than 50 people (including one U.S. service member) dead.

Security has deteriorated in the city over the past year, with U.S. security officials in Afghanistan recording more than 60 bombings in the latter half of 2015 and an increase in the use of truck bombs.

In December, one such attack targeted compounds used by U.S. government contractors, flattening security walls and buildings and leaving a 49-foot crater. Two people were killed and close to 40 were wounded.

“Threat of attack has already turned this capital into a cluster of forts, wrapped up in razor wire and concrete blast barriers, patrolled by a multitude of hard-faced men with guns. These days, when they cross town, senior Afghan and international officials often use helicopters as taxis, rather than run the risk of being shot or bombed while sitting in a traffic jam,” Reeves said. “It’s hard to know how you make this place any more secure.”