Train derailment in eastern Iran kills 21

Rescuers work at the scene of the derailment in eastern Iran (Iranian Red Crescent Society via AP)

At least 21 people died and a further 87 were injured when a passenger train travelling through eastern Iran struck an excavator and derailed nearly half its cars, officials have said.

The train derailment near the desert city of Tabas was the latest disaster to strike the Islamic Republic in recent weeks as Tehran struggles under US sanctions and any return to its nuclear deal with world powers remains in doubt.