(Updates toll of injured, gives details)

ROME, Oct 9 (Reuters) - One person was killed and at least 12 were injured in an explosion on Tuesday at a British-owned weapons factory outside Rome, emergency services said.

Police and the fire brigade said at least one of those hurt had suffered serious burns.

The blast appeared to have occurred in a part of the factory where there were deposits of magnesium, they said, but the cause was not immediately clear.

The plant at Colleferro, southeast of Rome, belongs to Simmel Defence, which manufactures ammunitions, explosives, missile warheads and rockets for the armed forces in Italy and abroad.

Simmel was bought by British company Chemring Group <CHG.L> in March this year.

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