At least 492 people have been killed in intense and wide-ranging Israeli air strikes targeting Hezbollah in Lebanon, in the deadliest day of conflict there in almost 20 years.

Thousands of families have also fled their homes as the Israeli military said it hit 1,300 Hezbollah targets in an operation to destroy infrastructure that the armed group had built up since the 2006 war.

Hezbollah, meanwhile, launched more than 200 rockets into northern Israel, according to the military. 

World powers have been urging restraint as both sides appear to be spiralling closer towards all-out war.

The Pentagon said it was sending “a small number” of additional US troops to the Middle East amid the growing crisis.