It was also the second consecutive day of attacks in the Afghan capital, undermining the ability of Afghan forces to keep security without help from NATO troops.
The attacker rammed his SUV into buses carrying court employees at the end of the day’ work. All of the dead were civilians, including women and children, police said, and at least 39 people were wounded.
The Taliban said they delivered a blow to “cruel judges” who obey Western powers, and warned of more bombings to come.
President Hamid Karzai condemned the attack, saying it was another “terrorist act that once again shows the Taliban are serving the enemies of Islam.”
Tuesday’s attack was the deadliest in Kabul since Dec. 6, 2011, when a suicide bomber on foot hit worshippers at a Shiite shrine, killing at least 80 people.
It came just a day after heavily armed fighters launched a failed assault on NATO’s operational headquarters at the military section of Kabul’s international airport. All seven attackers were killed by Afghan forces and only two civilians were wounded in Monday’s attack.
Hitting such high-profile targets as the Supreme Court or the international airport stirs up fear and threatens to shake confidence in Karzai’s government. The courthouse is on a busy main road in central Kabul, near the U.S. Embassy. The NATO headquarters is also nearby.
Tuesday’s blast went off as court employees were leaving the building from the back entrance, mostly in buses or private cars, said police officer Jahn Agha. Police spokesman Hashmat Stanikzai said the bomber specifically targeted the buses with court workers.
Taliban spokesman Zabiullah Mujahid claimed responsibility for the attack.
“The Islamic Emirate of Afghanistan was obligated to act against this puppet regime because the people have suffered under the courts,” said Mujahid, referring to the Taliban by the name they were known when they ruled Afghanistan. He warned of more such attacks if courts did not stop jailing insurgents.
As international forces started a withdrawal that will see most foreign troops gone by the end of 2014, the Taliban and other groups have unleashed a wave of bombings and assassinations around the country, testing the ability of Afghan security forces to respond with reduced help from NATO troops.
The Taliban have said they would go after government workers as part of their spring campaign targeting those serving in Karzai’s administration.
Despite an enormous security cordon around the capital, Kabul remains a prime target for insurgents.
On May 16, a suicide car bomber killed six Americans in a U.S. military convoy. Earlier that same day, heavily armed fighters attacked the compound of an international aid group in an upscale neighborhood, kicking off an eight-hour battle that killed two civilians and a police officer before all the militants were killed.
Authorities have said that Afghan forces have been able to fend off major attacks and have foiled several other plots, but the insurgents’ ability to strike Kabul has raised questions of whether violence will continue to soar.
A UN Security Council statement condemned Tuesday’s attack “in the strongest terms.”