Original sentence: According to some sources all started on October 19, when a Greek soldier ran after his dog, which had strayed across the border from Greece at the pass Demirkapia on Belasitsa (in Bulgarian)/Belles (in Greek); thus, it is sometimes referred to as the War of the Stray Dog.According to the newspapers of that time the town of Petrich was captured, but according to some other sources, the League of Nations sent a telegraph to both countries ordering them to stop their armies just few hours before Greeks launched their attack to Petrich.On the other hand according to other sources, the Greco-Bulgarian frontier incident was caused when Bulgarian soldiers violated the Greek borders, attacked a Greek outpost at Belasitsa/Belles and killed a Greek captain and a sentry.Some chetas of Internal Macedonian Revolutionary Organization (IMRO), together with the sentries, organised defence lines against the Greeks near Petrich.There are two versions of how the incident started.Volunteers and war veterans from the whole region were summoned to join the resistance
Edited sentence: A Greek officer attempting to affect a ceasefire was also killed.All started on October 19, when a Greek soldier ran after his dog, which had strayed across the border from Greece at the pass Demirkapia on Belasitsa (in Bulgarian)/Belles (in Greek); thus, it is sometimes referred to as the War of the Stray Dog.On  21 and 22 October  at the accident region were sent  Bulgarian troops: 6 infantry and 3 MG companies with 4 mountain and 8 field cannons, all of them of the 7th Rila Infantry Division.On 22 October 6th Greek infantry division crossed the border.On the 25th October Greek units tried to take Petritch but they failed due to resistance by the army, local voluteers and IMRO  detachments.The Bulgarian government alerted the UN in Geneva.The Greeks occupied 10 Bulgarian villages without any resistance: Kulata, Tchutchuligovo, Marino pole, Novo Hodozhovo, Dolno Spantchevo, Piperitza, Lehovo, Topolnitza, Marinokostino and Kartetchno.The League of Nations sent a telegraph to both countries ordering them to stop their armies just few hours before Greeks launched their attack to Petrich.The circumstances around the incident however, remained unclear