To "ignite" means to catch on fire. The word "ignite" describes just the moment when something first begins to burn. For example, a match "ignites" when you strike it.
You can use "ignite in the pattern "(someone) ignites (something):
She ignited each of the candles, one by one.
But you shouldn't use "ignite" without an object when talking about people, unless the people themselves are burning!