Lebanon's president said an investigation into the Beirut port warehouse explosion was looking at whether it was caused by negligence, an accident or possible external interference, his office cited him as telling local media on Friday.For all the latest headlines, follow our Google News channel online or via the app.“The cause has not been determined yet. There is a possibility of external interference through a rocket or bomb or other act,” President Michel Aoun said in comments carried by local media and confirmed by his office.He said the probe into Tuesday's blast at a warehouse housing highly explosive material was being conducted on three levels.“First, how the explosive material entered and was stored ... second whether the explosion was a result of negligence or an accident ... and third the possibility that there was external interference.”Read more:Twitter flags fake video showing missile striking Lebanon portSixteen arrested in connection with Beirut blasts: State-run news agencyUS pledges over $17 mln in disaster aid for Lebanon
Source: Al Arabiya
Full Article: Beirut explosion cause unknown, possibility of external interference: President