Wednesday's attack, which detonated two-way radio devices, wounded about 450 people but was responsible for 25 deaths, twice as many as in Tuesday's blasts.

Icom told the BBC it was aware of reports that two-way radio devices bearing its logo had exploded in Lebanon, and said it was investigating the matter.

In the days when citizens band radio, a two-way radio system, was big, a young, unpublished Saul had an idea: a thriller involving CB radio and truckers.

That two-way radio gave the chain its name: In-N-Out Burger.

Assistant Principal Kristy Gibson-Marshall, who had a two-way radio that day, said she told others: “I have eyes on the shooter.”