(Updates details on French fire, weather alert)

* Wildfires rage in southwestern France, Spain

* Health officials report hundreds of heat-related deaths

* UK emergency committee to meet after weather warning

By Layli Foroudi and Sergio Goncalves

PARIS/LISBON, July 16 (Reuters) - Wildfires raged in southwestern France and Spain on Saturday, forcing thousands of people to be evacuated from their homes as blistering summer temperatures put authorities on alert in parts of Europe.

About 14,000 people had been evacuated from France's Gironde region by Saturday afternoon as more than 1,200 firefighters battled to bring the flames under control, regional authorities said in a statement.

"We have a fire that will continue to spread as long as it is not stabilised," Vincent Ferrier, deputy prefect for Langon in Gironde, told a news conference.

Wildfires have torn through France in recent weeks, as well as other European countries including Portugal and Spain, and more than 10,000 hectares (25,000 acres) of land was on fire in the Gironde region on Saturday, up from 7,300 hectares on Friday.

In the latest weather warning, 38 of France's 96 departments were listed on "orange" alert, with residents of those areas urged to be vigilant. The heatwave in western France is expected to peak on Monday, with temperatures climbing above 40 degrees Celsius (104 Fahrenheit).

In neighbouring Spain, firefighters were battling a series of blazes on Saturday after days of unusually high temperatures that reached up to 45.7 C (114 F).

The nearly week-long heatwave has caused 360 heat-related deaths, according to figures from the Carlos III Health Institute.

More than 3,000 people have been evacuated from homes due to a large wildfire near Mijas, a town in the province of Malaga that is popular with northern European tourists, the region's emergency services said in a tweet early on Saturday.

Many were taken to shelter in a provincial sports centre.

"The police drove up and down the road with their sirens on and everyone was told to leave. Just leave. No instructions where to go," said British pensioner John Pretty, 83.

"It's frightening ... because you don't know what's happening," said Belgian resident Jean-Marie Vandelanotte, 68.

Elsewhere in Spain, thick black plumes of smoke rose into the air near Casas de Miravete in the Extremadura region as helicopters dumped water on flames that have scorched 3,000 hectares, forced the evacuation of two villages and threatened to reach the Monfrague national park.