I wonder whether the following Surrey Mirror article of 5th March 1915, refers to the accident in this photo:

Territorials Injured

Accident to a Reigate Motor ?bus

An extraordinary accident occurred in the High-street, Reigate, on Tuesday evening, resulting in serious injury to two Territorials and minor injuries to three others. It appears that a party of men of the 19th County of London Regiment were drawn up by the side of the roadway opposite the Battalion Stores. A double-decked ?bus of the East Surrey Traction Company was proceeding along the High-street, Reigate, towards West-street, when the steering wheel of the ?bus failed, and the vehicle ran into the Territorials. Several of the men were knocked down, two of them being seriously injured. These two, Ptes. Birch and Atkinson were conveyed on a R.A.M.C. motor ambulance to the Red Cross Hospital at Hillfield, Reigate, and three other men, Ptes. Savage, Suckey, and Toole, were taken to their billets. The men were first attended to by their regimental doctor, and members of the R.A.M.C. also rendered assistance. The driver of the ?bus was George E. Purchase, and when he found his steering wheel was out of order he at once applied his brakes, but could not pull up in time to prevent the ?bus swerving into the men.

Upon inquiry it was ascertained that all the men were progressing satisfactorily.

This is East Surrey's fleet No 129, an AEC chassis with a Ransomes body. Introduced in July 1924 it was withdrawn in September 1931

Another vehicle on loan from the LGOC, this time fleet number 77,reg No PE1417, an AEC chassis with an LGOC body. It entered service in April 1925 and was returned off loan in may 1930.

One of six private hire coaches bought in 1927 with ADC chassis and Shorts bodywork

Another vehicle on loan from LGOC, originally K365 it became No 104 in the East Surrey fleet in June 1923 and was returned off loan in May 1930

A wonderful view of London Transport STL994 reg No BLH865, introduced in 1935 from Chelsham garage for route 403. It ran from there until 1947 and was finally withdrawn in 1949