A huge explosion rocked the Lebanese capital Beirut on Tuesday, shaking buildings, shattering windows and sending a huge plume of smoke into the sky, AFP correspondents said.

Lebanese media carried images of people trapped under rubble, some bloodied, after the massive explosion, the cause of which was not immediately known.

The loud blast in Beirut's port area was felt across large parts of the city and some districts lost electricity.

Beirut blast
The blast in Beirut's port area sent a huge plume of smoke into the sky Photo: AFP / Anwar AMRO

Preliminary reports by local Lebanese media said the blast may have been the result of an incident at Beirut port.

"Buildings are shaking," tweeted one resident, while another wrote: "An enormous, deafening explosion just engulfed Beirut. Heard it from miles away".

Online footage from a Lebanese newspaper office showed blown out windows, scattered furniture and demolished interior panelling.

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