A coach from Sétif skidded off a road and fell into a ravine in Boumerdès, northern Algeria, on July 31, killing at least 27 people and injuring 42; President Tebboune declared three days of national mourning; within 24 hours a second bus crash at Timimoune, in the Saharan south, killed three more and injured 20, prompting Algerian press to demand radical reform of road transport regulation