The huge explosion in Lebanon's capital, Beirut, blew out the windows of the CNN bureau, according to CNN's correspondent Ben Wedeman, who said he saw a cloud of red smoke drift over the city after the blast.
Wedeman said he had "never felt anything like it ... [I've] been around the block and seen pretty large explosions ... and this was bigger," he told CNN's Becky Anderson, adding that he only heard and felt one explosion.
"As far as I can tell there was just one absolutely massive explosion which caused all this damage in the Lebanese capital."
Lebanon's state-run NNA news reports that a major fire broke out in a warehouse used for storing firecrackers, near Beirut's port, and strong explosions were heard shortly afterwards.
Wedeman said the cause of the blast was "still not clear -- if it was fireworks, as some news sources are saying -- they are some damn big fireworks."
Watch CNN's Ben Wedeman from the scene: