"On August 17, 1916, the Bulgarians, who, at the end of May, had entered Greek territory by the Struma Valley and moved down as far as Demir Hissar, continued their advance into Greek Macedonia. Columns of all arms advanced from seven different points, between Sarisaban, on the Mesta, and Demir Hissar. The four eastern columns converged on the country about Drama and Kavala, while the remainder moved southward on to the line of the Struma from Demir Hissar toward Orfano. On August 19, 1916, a mounted brigade with one battery carried out a strong reconnoissance, and found the enemy in some force on the line Prosenik-Barakli Djuma; on the following day, after being reinforced by a battalion, this brigade again advanced in conjunction with the French detachment. These attacking troops, after encountering the enemy in force on the line Kalendra-Prosenik-Haznatar, withdrew after dark to the right bank of the Struma. The French detachment was subsequently placed under the orders of the General Officer Commanding British troops on this front, and received instructions to cooperate in the defense of the river line.
[Sidenote: Bridges over Angista River destroyed.]
"On August 21, 1916, the railway bridge near Angista Station was demolished by a detachment from the Neohori garrison, and three days later two road bridges over the Angista River were destroyed. Both these operations were well carried out by yeomanry, engineers, and cyclists in the face of hostile opposition.
[Sidenote: Bulgarians in Eastern Macedonia.]
"The Bulgarians continued their advance into Eastern Macedonia unopposed by the Greek garrison, and it was estimated that by the end of August the enemy's forces, extending from Demir Hissar southward in the Seres sector of the Struma front, comprised the complete Seventh Bulgarian Division, with two or three regiments of the Eleventh Macedonian Division, which had moved eastward from their positions on the Beles Mountain to act as a reserve to the Seventh Division, and at the same time to occupy the defenses from Vetrina-Pujovo northward. Opposite the Lower Struma was a brigade of the Second Division, with a brigade of the Tenth Division, in occupation of the coast and the zone of country between Orfano and the Drama-Kavala road. This brigade of the Tenth Division was supported by another brigade in the Drama Kavala area. As a result of this advance and of a similar move in the west General Sarrail decided to intrust to the British Army the task of maintaining the greater portion of the right and center of the allied line.