An explosive device planted under an overpass in Istanbul's district of Maltepe injures four people.
A bomb blast wounded four people overnight Sunday in Istanbul, said security sources.
The wounded, two passengers in a car and two pedestrians waiting for a taxi, were hit by metal pieces after the explosive went off under an overpass in the city's Maltepe district on the Asian side.
Medical sources gave no information about how seriously hurt the wounded were.
Some cars that were passing by were also damaged in the blast.
It was also not clear who planted the explosive, as responsibility was not claimed by any group but police say they have launched an investigation into the incident.