ellos incendiaron

set on fire, burned down

→ incendiar
incendi to set fire to, to ignite + aron 3rd-person plural past tense
verb · third plural · past indicative Rare #40,575
set on fire, burned down Third-person plural preterite (they).
SP: Los manifestantes incendiaron varios autos en la calle.
EN: The protesters set several cars on fire in the street.
Conjugation of incendiar
Indicative past
SingularPlural
Third — incendiaron

Diez casas se incendiaron.

Ten houses caught fire.

Incendiaron la cabaña.

They set fire to the cabin.

Ustedes son los que incendiaron los almacenes.

You are the ones who set fire to the warehouses.

— R.A.F. Facción del ejército rojo (2008)

Incendiaron el traje AMP.

They set fire to the AMP suit.

— Avatar (2009)

Antes de irse sus hombres incendiaron la ciudad.

Before leaving, his men set the city on fire.

Ellos incendiaron la casa del vecino en venganza.

They set the neighbor’s house on fire in revenge.