JERUSALEM, April 14 (Xinhua) -- One Israeli soldier was killed and three others injured in a tank accident early Saturday near the Nitzana border crossing between Israel and Egypt's Sinai Peninsula.

Two of the injured soldiers were in serious condition, the Israeli army said in a statement.

Initial investigation showed the tank deviated from its planned path and fell into a river bed, according to Israeli media reports.

The cause of the deviation is still unclear.

The fall caused a shell to ignite, which set off the tank's fire suppression system. The soldier was likely killed in the flames.

The tank was sent to the area as part of an operation to foil a suspected terror attack, local media said.