An explosion at a border crossing between Syria and Turkey on Thursday killed more than 40 people and left scores wounded, activists said.
The blast ripped through the Bab al-Salameh crossing about 30 miles north of the city of Aleppo. It was caused by about 1 ton of explosives that were in a van parked in a garage and apparently were remotely detonated.
The Syrian Observatory for Human Rights, a British-based opposition group with a network of activists in Syria, reported that 43 people were killed, including five women and three children. That number was likely to rise because many of the wounded were in critical condition, the group said.
One of two border crossings between Turkey and the northern province of Aleppo, Bab al-Salameh represents a vital link for Syrians residing in the Turkish cities of Kilis and Gaziantep, many of them refugees. The explosion occurred in the early afternoon, a peak time for the hundreds of travelers going between the two countries before the weekend.
"I was heading to the crossing when I saw a big bloom of fire followed by a very strong quake," Abu Yazid Halaby, a media activist based in the nearby city of Azaz, said via Skype. "When I got there, there were body parts strewn around and people panicking everywhere.... I'm still shaken by the horror of the scene."
This is not the first time crossings on the Turkish-Syrian border have been targeted. A similar car bomb attack in February killed six people.
Although no group immediately claimed responsibility, many suspected the extremist Islamic State of Iraq and Syria, which often uses car bombs in its attacks. The militant group, which had controlled Bab al-Salameh and Azaz until recently, was forced to relinquish control after a large-scale purge by rival rebel fighters.
Activists also reported receiving threats targeting the crossing.