A massive explosion has ripped through a power plant in the United States, causing serious damage although it is now unclear whether anybody was killed.

Shortly after the blast police said two people had died but more recent reports suggest that statement has been retracted.

The explosion happened at 11.30 am Sunday morning, during tests at the 620 megawatt gas-fired power plant near Hartford, Conneticut. It is still under construction and was due to come online in the summer.

It is thought around 100 people were working at the plant at the time, but the blast was felt up to 50 kilometres away.

Local media talk of up to 250 people being injured and an eye witness described seeing “bodies everywhere”.

The reason for the explosion is still under investigation.

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