(CNN) -- A 5.5-magnitude earthquake shook northern Algeria on Friday, knocking houses to the ground and injuring 15 people.
Oran, the largest city in the region, received most of the impact of the quake, which had an epicenter about 30 km (18.6 miles) north in the Mediterranean Sea. The quake hit at about 9 p.m. (4 p.m. ET).
Several old homes in the downtown neighborhood of Gambeta were destroyed and 15 people were injured, according to a local government spokesman.
Residents fled their homes and mingled in the streets -- although many simply went about their business because of the moderate strength of the quake, the spokesman said.