A suicide bomber blew himself up inside a historic judicial building in Damascus on Wednesday, Syrian state media said. It was the second mass-casualty attack in five days in the heart of the Syrian capital.
The head of the Damascus police, Mohammed Kheir Ismail, told Syrian state television that the attacker arrived at the building wearing a military uniform and carrying a rifle and hand grenades. When guards took away his weapons and began to search him, he rushed into the building and detonated an explosives belt.
“This is a dirty action, as people who enter the palace are innocent,” said Ahmad al-Sayed, Syria’s attorney general, adding that the attack appeared intended to kill a large number of people.
Syrian state media broadcast images of pools of blood on the building’s marble floor and said at least 30 people had been killed. The Syrian Observatory for Human Rights, which opposes the government and tracks the Syrian conflict from Britain, said at least 39 people were killed, including seven police officers and guards.
The attack coincided with the sixth anniversary of the start of the popular uprising against President Bashar al-Assad, which began with demands for political change and evolved into the current multisided conflict.
After the government used overwhelming force to suppress protests, some of them near the site of Wednesday’s attack, many in the opposition took up arms. As the rebels wrested control of territory from the government, jihadist organizations like Al Qaeda and the Islamic State took advantage of the chaos, setting up operations and gradually displacing the rebel groups backed by Western and Gulf countries.
The war has now left more than 400,000 people dead and displaced about half of Syria’s people. Repeated rounds of international peace talks have failed, while military aid from Russia and foreign Shiite militias has helped Mr. Assad reclaim significant parts of the country from the rebels, including Syria’s largest cities and the areas where most of the remaining people are living.
Throughout the war, Mr. Assad has sought to maintain popular support by portraying the rebels as terrorists and by maintaining security in the areas he controls. Those areas, though heavily damaged in some cases, are generally safer for civilians than rebel-held zones, which are frequently bombed by government jets.
However, the recent attacks show that even areas solidly in the government’s grip remain vulnerable, and they raise questions about how jihadist groups could have circumvented government security.
Syrian state television said there was a second suicide attack on Wednesday in a restaurant in western Damascus, but did not immediately report about casualties. A television station run by Hezbollah, the Lebanese Shiite militia allied with Mr. Assad, reported two other blasts elsewhere in the city.
No group immediately claimed responsibility for the bombing at the judicial building, the Palace of Justice. The building is just outside the Old City of Damascus, a few hundred yards from Shiite shrines that were the site of a double bombing on Saturday; that attack killed more than 50 people, many of them pilgrims from Iraq.
A rebel group that includes the Syrian affiliate of Al Qaeda claimed responsibility for the Saturday attack, saying the explosions near the shrines were aimed at Iranian and local militias fighting on Mr. Assad’s side. The rebel group, the Levant Liberation Committee, said there would be more attacks.
“This operation, and those like it, is a clear message to the Iranian militias that the truth cannot be forgotten, the ground cannot be lost and the oppressor will have his day,” the group said in a statement released on Sunday on social media.