A preliminary investigation by Lebanese authorities into the communications devices that blew up in Lebanon this week found that they were implanted with explosives before arriving in the country, according to a letter sent to the U.

At least 20 people were killed and another 450 were wounded, the Health Ministry said, in this apparent second attack.

Hezbollah officials and Lebanon's state media say explosions went off in Beirut and multiple parts of Lebanon in an apparent second wave of detonations of electronic devices