Explosions Rock Istanbul Soccer Stadium, Killing 38, Wounding 155

Enlarge this image toggle caption Cansu Alkaya/AP Cansu Alkaya/AP

Updated at 10:52 a.m. ET Dec. 11

Turkey has declared a national day of mourning after two explosions struck a large soccer stadium in Istanbul, leaving at least 38 people dead and 155 others wounded, according to the Turkish interior minister. Among those killed were 30 police officers.

The Kurdistan Freedom Falcons, or TAK, released a statement claiming responsibility for the massive car bomb, which detonated outside the Besiktas stadium well after it had emptied of fans. The attack targeted the dozens of riot police stationed outside.

The stadium had played host to a game between the teams Bursaspor and Besiktas earlier Saturday. In a tweeted statement, the Turkish soccer team Bursaspor said that none of its fans appear to have been harmed in the attack.

The Turkish transport minister, Ahmet Arslan, tweeted that the explosion was a terrorist attack.

"I condemn the terror attack on Besiktas, Istanbul, and wish all those injured a speedy recovery," Arslan said, according to The Guardian.

TAK, the Kurdish militant group, grew out of another organization that has long mounted a violent campaign against the Turkish government, reporter Dalia Mortada tells NPR's Newscast unit: "The group is an offshoot of the outlawed Kurdistan Workers' Party, or PKK, which has been spearheading a violent campaign for Kurdish rights for decades," Dalia reports.

On Sunday, President Recep Tayyip Erdogan promised the government would continue to fight against terrorism "until the end," reports the AP.

Saturday's violence comes at a time of prolonged political upheaval in Turkey. As reporter Teri Schultz reported, a failed military coup attempt in July has been followed by months of purges across Turkish society:

"Some 110,000 government bureaucrats, teachers, journalists, soldiers and others have been detained, fired or suspended from their jobs in Turkey on suspicion of aiding or sympathizing with the coup attempt."

Among them are hundreds of Turkish military personnel working for NATO, who have been accused of participating in the failed ouster of President Recep Tayyip Erdogan.

At the same time, CNN reports that Turkey has been hit with violence from several different angles:

"ISIS militants have mounted a series of devastating bombings that have claimed the lives of hundreds of Turks. "Meanwhile, Turkish security forces continue to clash on a nearly daily basis with PKK militants, mostly in predominantly Kurdish parts of southeastern Turkey."

Just last month, a car bomb killed eight people in Diyarbakir, the largest city in the majority-Kurdish southeast.

Meantime, the AP reports that Turkey's prime minister's office has imposed a temporary blackout on coverage of Saturday's explosion: