Afghan security forces inspect site of suicide car bombing in Kabul, May 19, 2015.
Afghan security forces inspect site of suicide car bombing in Kabul, May 19, 2015.

ISLAMABAD - A Taliban suicide car bomber struck Tuesday near Afghanistan’s Justice Ministry in a busy section of downtown Kabul, killing at least four people and wounding more than 50 others.

Afghan police and hospital officials say the device exploded in the ministry's car park where many employees gather to board minibuses at the end of the work day.

"A police investigation has concluded a suicide bomber in an explosives-packed car detonated the device," Interior Ministry spokesman Sediq Sediqi said in Dari.

The attack, which claimed mostly civilians, is the latest of several targeting employees of the Afghan justice system in the past month. A series of deadly blasts have rocked the Afghan capital this week, intensifying fears of a bloody fighting season.

In a statement sent to reporters, a Taliban spokesman Zabihullah Mujahid claimed responsibility for the bombing, saying it was aimed at officials of the “slave” Afghan judiciary.

The spokesman also said the violence is meant to avenge what he called “injustices, mistreatment and torture” being inflicted on Afghan prisoners by the U.S.-backed Kabul administration and its judiciary. He warned of more such attacks to come.

Earlier this month, another Taliban suicide bomber in Kabul rammed a bus carrying Justice Ministry employees, killing five prosecutors and wounding more.

The United Nations, which as condemned the wave of violence targeting civilians and professionals as potential war crimes, has documented a record increase in civilian casualties this year in Afghanistan compared to the same period in 2014.

The Islamist insurgents have ramped up attacks in Kabul and across a wide area of the country since late last month, when they announced the start of their annual spring offensive.

For the first time in the decade-long hostilities, Afghan security forces are battling the insurgents after NATO terminated its combat mission and withdrew most of its forces from Afghanistan in December.

Analysts predict this could be one of the bloodiest years in the Afghan conflict.

“This summer we are seeing before our eyes, in my opinion, the worst offensive that the Taliban have ever launched in Afghanistan," said Ahmed Rashid, a Pakistani author of several best-selling books about Afghanistan and Central Asia.

"It is affecting all four corners of the country. Previously, when the Americans and NATO forces were there, most of the fighting was taking place in southern and eastern Afghanistan. Today, it is taking place in the north and the west and it has put enormous pressure on the Afghan army,” he said.

Last week a Taliban gun-and-bomb attack on a guest house in Kabul killed 14 people, including nine foreigners.

On Sunday a Taliban bomber rammed his car into a convoy of the European Union Police advisory mission in Afghanistan. The attack near the Kabul airport killed a British security contractor and two young Afghan girls.