A series of loud explosions and gunfire has rocked the Afghan capital of Kabul on Tuesday.
The violence is centered in a central neighborhood of Kabul, near the city's embassy district.
The Taliban has claimed responsibility for the attack, telling news agencies it is targeting a government building and the country's intelligence service.
There are no immediate reports of casualties.
Meanwhile, U.S. officials say they believe the Pakistan-based Haqqani network was behind the powerful truck bomb blast at a NATO base in central Afghanistan that killed four Afghan civilians and wounded more than 100 others, including 77 U.S. troops.
The Taliban claimed responsibility for Saturday's attack outside the main gate of the Combat Outpost Sayed Abad in Wardak province. But Pentagon spokesman George Little said Monday there is a very strong likelihood that Haqqani leadership supported and was aware of the attack.
The militant Haqqani network, which operates from Pakistan's North Waziristan tribal region and is affiliated with both the Taliban and al-Qaida, has launched a number of high-profile attacks in neighboring Afghanistan.
The explosion occurred on the eve of the 10th anniversary of the September 11 terror attacks against the United States.