Turkish authorities on Sunday investigated a pair of secondary crashes at emergency sites that killed at least 35 people the previous day. In both cases, first responders tending to earlier collisions were among the dead.
Saturday's tragedies happened just 250 kilometers (155 miles) apart in southern Turkey. The first happened on the highway between Gaziantep and Nizip when a passenger bus collided with emergency teams that had responded to a crash in Mardin Province, west of Derik.
Three firefighters, two paramedics and two journalists were among the 15 people killed, according to Interior Minister Suleyman Soylu, Eight of the victims were from the bus, he said.
The Ilhas News Agency said two of its journalists were killed after pulling over to offer help to people involved in the initial accident, in which a car came off the highway and slid down an embankment.
Television footage showed an ambulance with severe rear damage and the bus turned on its side along the highway. Gaziantep Gov. Davut Gul said 22 people were injured in the secondary crash.
The other incident happened late Saturday afternoon in Derik after the brakes of an articulated truck failed, causing it to crash into two other vehicles near a gas station.
As first responders worked at the scene and crowds gathered to watch, another truck lost control and ploughed into them.
Speaking from the site, Soylu said 20 people were killed and 26 injured. A police officer was among the victims, and two drivers were detained as an investigation was launched, he said.
Turkey has a poor record of road safety. Some 5,362 people died in traffic incidents last year, according to the government.
