MARIUPOL, Ukraine (AP) — With bodies piling up in Russia's nine-day siege of Mariupol, the port city of 430,000 in southeastern Ukraine, local authorities are hurrying to bury the dead in a mass grave.

City workers made quick signs of the cross gestures as they pushed bodies wrapped in carpets or bags into a deep trench some 25 meters (80 feet) long on the outskirts of the city.

More than 70 bodies have been interred in the common grave since it was opened Tuesday.

About half of those buried were killed in the intense shelling of the city, estimated an AP journalist who visited the burial ground. Others died at home from natural causes, but authorities were unable to arrange for the collection of the bodies or their burial.

Mariupol has suffered at least 8 major airstrikes in the past 48 hours, with a children's hospital and the central fire department among those hit.

City residents are staying in shelters as much as possible as temperatures dip to minus 9 degrees Celsius (15 degrees Fahrenheit).