Anger over a Somali-born teen’s failed plan to blow up a van full of explosives during a US Christmas tree lighting ceremony erupted today when a fire damaged an Islamic centre frequented by the suspect.

A teenager plotted "a spectacular show" of terrorism for months, saying he did not mind that children would die if he bombed a crowded Christmas tree lighting ceremony, court documents reveal.

Undercover agents foiled a plot by a Somali-born teenager to carry out a car bomb attack at a crowded Christmas tree lighting ceremony in Portland, Oregon, prosecutors said today.