An investigation has been launched after a car crash injured 13 spectators at the Network Q Rally of Great Britain.

A 13-year-old girl will undergo surgery for injuries after a car driven by Spain's Carlos Sainz ploughed into a group of spectators on Saturday.

The accident happened in the Brechfa forest, near Carmarthen, in west Wales, on special stage 11 of the rally which finishes in Cardiff on Sunday.

Organisers scrapped the 11th and 12th stages on Saturday, although the rally later resumed with Richard Burns edging closer to becoming the first Englishman to win the world title.

Rally officials said nine people with minor injuries were discharged from West Wales General Hospital in Carmarthen on Saturday night.

"A 12-year-old boy with severe bruising is expected to leave hospital today," said rally spokesman John Horton on Sunday.

"A 13-year-old girl is still in hospital and is expected to have surgery on a lower limb injury.

"One adult with head injuries is expected to be discharged later today and the adult with back injuries will be staying in hospital for another night."

Two air ambulances were deployed to take the injured to hospital after Sainz's Ford Focus went straight on at a bend and hit another car and the group of spectators.

The two-time world champion was withdrawn by his team from the rally at the end of the stage.

The investigation will be carried out by the Motor Sports Association, the sport's governing body in Britain.

A report will be made to FIA, motor sport's world governing body.

"The Network Q Rally of Great Britain employs stringent safety procedures, including the use of three spectator control and safety cars who go through each stage in advance of the competitor cars," added Horton.

"Every stage is also inspected by the FIA Safety Delegate who has the power to recommend the cancellation of a stage if not satisfied with the safety standards.

Safety scrutiny

"Additional spectator safety scrutiny is conducted by the MSA's own Health and Safety Executive and the Spectator and Event Safety Manuals run to over 200 pages.

"The Motor Sports Association has already begun the procedures for a thorough investigation of the incident.

"Any recommendations made following this will be implemented for next year's event."

About 200,000 people watch the rally each year with many of the timed special stages taking place on Forestry Commission gravel roads.

The entire rally took place in Wales this year with the Brechfa stage being used twice.

Officials are understood to have obtained video film from inside Sainz's car.

His withdrawal guarantees a British world champion, with sidelined Scot Colin McRae the only alternative winner to Burns.