12 December 2011 Last updated at 12:31 ET

Iran steel factory blast: Foreigners among seven killed

A local MP said there appeared to have been unexploded munitions in the consignmnt of scrap

An explosion at a steel factory in Iran has killed seven people including foreign nationals, say reports in Iranian state media.

The blast in the city of Yazd was caused by discarded ammunition which arrived at the plant with a consignment of scrap metal, the official Irna news agency reported.

It happened late on Sunday at the privately owned plant, Irna said.

At least 12 other people are reported to have been injured.

The governor of Yazd region in central Iran, Azizollah Seyfi, said "several of those killed were foreign nationals".

He gave no further details of their nationalities or what caused the blast, although he did say it was being investigated.

A local member of parliament, Ali Akbar Oliaw, said there appeared to have been unexploded munitions in with the steel.

"Among the scrap metal was ammunition which had not worked, and this caused the blast," he was quoted as saying.

Unexplained blasts

There have been several unexplained explosions in Iran so far this year at factories and military sites, fuelling rumours of foreign intelligence involvement designed to disrupt Iran's nuclear programme.

A powerful blast in November killed 17 people at a military base near Tehran belonging to Iran's elite Revolutionary Guards.

Israel later said that explosion could have slowed down Iran's nuclear activities.

A further blast was reported at a factory in Isfahan province on 28 November.

The causes of these incidents remain unclear.

Iran denies trying to make an atomic bomb and says its nuclear activities are purely peaceful.