Lebanon’s health ministry said at least eight people were killed and over 2,700 others were wounded across the country on Tuesday when their handheld pagers exploded.
Those injured include medics and Hezbollah fighters.
The armed group has blamed Israel for the detonations which one official has described as its “biggest security breach” in nearly a year of war with Israel.
The two have been engaged in cross-border warfare since the conflict in Gaza erupted last October.
The Israeli military has not commented on the incident.
Hezbollah’s leader a few months ago called on the group’s fighters to stop using smartphones saying Israel had the technology to track these devices.
It is not immediately clear how the pagers were detonated.
The health ministry has called on all medical personnel to head to their respective hospitals to help cope with the massive numbers of wounded.
It has also urged healthcare workers and others with pagers to discard them.