In a telegram sent today by Vatican Secretary of State Cardinal Angelo Sodano, the Pope expressed "his profound sympathy to the authorities and Iranian people, again in mourning because of this railway catastrophe."

The explosion occurred Wednesday, hours after runaway train cars carrying fuel, industrial chemicals and cotton derailed, overturned and caught fire near Neyshabur, in northeastern Iran.

Iranian authorities said the figure of the dead had risen to 309, and that the number of injured might reach 500, the Efe agency reported.

In the telegram, the Pope invoked "the blessing of the Most High" for all those affected by the accident, especially the wounded and those assisting them.