Victims are waiting to be loaded into an ambulance at the scene of a suicide car bomb attack in Kabul, Afghanistan, Wednesday, Jan. 16, 2013. Six militants - one driving a car packed with explosives - attacked the gate of the Afghan intelligence service in the capital Kabul on Wednesday, setting off a blast that could be heard throughout downtown and which sent a plume of dark smoke rising into the sky. AP Photo/Ahmad Jamshid A security man with the Afghan intelligence services stops a vehicle, unseen, at the scene of a suicide car bomb attack in Kabul, Afghanistan, Wednesday, Jan. 16, 2013. AP Photo/Musadeq Sadeq Afghans load a victim into an ambulance at the scene of a suicide car bomb attack in Kabul, Afghanistan, Wednesday, Jan. 16, 2013. Afghans load a victim, right, into an ambulance at the scene of a suicide car bomb attack in Kabul, Afghanistan, Wednesday, Jan. 16, 2013. Security men with the Afghan intelligence service are seen at the scene of a suicide car bomb attack in Kabul, Afghanistan, Wednesday, Jan. 16, 2013. KABUL, Afghanistan (AP) - Taliban suicide bombers attacked the gates of the Afghan intelligence agency Wednesday, killing one person and wounding dozens in a blast that shredded nearby cars and shattered storefront windows three blocks away. The brazen midday attack highlighted ongoing violence in Afghanistan and the determination of the insurgency to continue fighting even as President Hamid Karzai and the U.S. negotiate for a quicker pullout of American forces. A minivan drove into a gate of the intelligence agency compound in the capital at noon and exploded in a blast that was heard throughout downtown. A second minivan pulled up, and five attackers wearing explosive vests jumped out and tried to storm the gate, police said. Security forces killed the five attackers and defused explosives found in the second van, police said in a statement. It was the second attack targeting the intelligence agency in as many months. On Dec. 6, a Taliban suicide bomber posing as a peace messenger blew himself up while meeting with Afghan intelligence chief Asadullah Khalid inside a Kabul residence. Khalid has been hospitalized in the United States with serious wounds since then. Taliban spokesman Zabiullah Mujahid claimed responsibility for the latest assault in a text message sent to The Associated Press. The Taliban insurgency regularly targets Afghan army and police, but attacks against the intelligence agency show the group's ability to strike even those who are supposedly closely monitoring their activities. One intelligence service guard was killed in the blast, said agency spokesman Shafiqullah Tahiri. He did not provide any information on guards who were wounded. Mohammad Zahir, the chief of the Kabul police investigation unit, said at least 30 people suffered injuries. Tahiri said some of those injuries were minor, but four of the wounded were in critical condition. The attack comes less than a week after Karzai returned from a trip to the United States in which he pushed the U.S. to get its troops out of Afghan villages. During the visit, both sides seemed ready to consider a much smaller American force in Afghanistan after 2014 than had previously been envisioned. Karzai said on his return that Afghanistan would be safer once the U.S. troops leave. But Wednesday's attack was a stark reminder that Afghan forces are as much a target as foreign troops. After Wednesday's blast, ambulances were able to carry some of the wounded to hospitals, while others were loaded into the back of a pickup truck. Blood streamed down the face of one man, staining his white-collared shirt and sweater vest as he waited for an ambulance. The blast left the twisted wreckage of at least seven cars on the street, while the windows of nearby shops were blown out and glass shards littered the pavement blocks away. A heavy snow started to fall as uniformed intelligence agents cordoned off the area around the gate. The blast walls at the entrance were blackened from the explosion and metal pieces - apparently the remains of the entrance gate - were twisted and strewn about. The entire intelligence service compound is surrounded by tall, thick cement walls designed to protect buildings from bomb blasts. Attacks in the heavily secured Afghan capital are less common than in the country's restive south, but they do occur and are often more sophisticated operations. They frequently include multiple attackers trying to penetrate the perimeter of armed guards and blast walls that surround government buildings and embassies. That blast killed at least two Afghan workers and wounded more than a dozen people. A spokesman for the international military coalition, Maj. Martyn Crighton, said Afghan forces responded to the attack and that NATO forces were not involved. Associated Press writers Amir Shah, Patrick Quinn and Rahim Faiez contributed to this report in Kabul.