A bus belonging to Orascom Group was transporting 56 employees slipped Saturday morning into Mariotiya river canal in Giza leading to at least 10 deaths, according to the Egyptian health ministry.
Al-Ahram Arabic news website had reported earlier that 25 died in the accident.
Bodies were pulled from the water while civil protection forces are trying to retrieve more bodies believed to have sunk. The death toll is likely to rise, Ahram Online reported.
Local security forces sent a winch to pull the bus from the lake and the road was blocked.
Traffic accidents, which official statistics say claim 18 lives a day, are commonplace in Egypt due to ill-maintained roads and railways as well as disregard for traffic laws.
Earlier in March, seven people were killed — including children — and 26 others injured in a collision between a school bus and a train on a highway connecting Cairo to the northeastern city of Ismailia.