On Saturday an explosion ripped through a power plant in the Iranian city of Ahvaz, marking the third 'mystery' blast to hit the country in only under a week, and the fourth recently.
State media showed emergency crews on the scene of the daytime incident while a fire raged at the power plant. This followed days ago a huge blast which destroyed Sina hospital in northern Tehran, which killed 19 people and injured 14.
Iranian authorities had described the Sina blast as the result of a gas leak. A similar explanation was offered for other prior explosions.
To review, starting over a week ago a massive explosion was observed lighting up the midnight sky outside Tehran, caught on film by local residents, which Iran's military dismissed as a gas leak explosion incident. But it was later revealed to have occurred at a ballistic missile development facility.