Hezbollah leader says device attack crossed 'red line,' fears of war mount

The leader of Hezbollah on Thursday said this week's deadly attack on the Lebanon-based militant group's communications devices was a severe blow that crossed a red line.

Hassan Nasrallah said the group is investigating how the two-day attack, which killed more than 30, wounded thousands and was widely believed to be carried out by Israel.

Yes, we were subjected to a huge and severe blow, Nasrallah said. The enemy crossed all boundaries and red lines," he added.

As usual, Nasrallah spoke by video from an undisclosed location. Hezbollah typically convenes a rally for supporters to watch his speeches on a big screen, but this time they did not.