Spanish firefighters were Thursday working to extinguish two huge wildfires which have wreaked havoc on the Canary Islands of Gran Canaria and Tenerife, according to DPA. The fires on both islands were under control after circling a total area of 35,000 hectares, much of which burned down. Local officials expected the blazes to be extinguished by the week-end. Nearly 14,000 people were evacuated, but the vast majority of them had returned home by Thursday. Police were searching for a possible arsonist on Tenerife, where the fire was believed to have been started intentionally. On Gran Canaria, a forest warden was in custody after confessing to starting the fire there over not getting his work contract renewed. Fires destroyed more than 160 houses and an estimated one third of the forested surface on the two islands. Prime Minister Jose Luis Rodriguez Zapatero promised damages to affected families when visiting the Canaries on Wednesday. Meanwhile, a 44-year-old woman was killed while participating in a firefighting effort near Teruel in the north. A tree crashed on the woman during a wildfire which consumed 1,000 hectares. The blaze was reported under control.