the wider Rumeli Eyalet (Balkans) until 1826, and subsequently the capital of Selanik Eyalet (after 1867, the Selanik Vilayet). This consisted of the sanjaks of Selanik, Serres and Drama between 1826 and 1912. With the break out of the Greek War of Independence in the spring of 1821, the governor Yusuf Bey imprisoned in his headquarters more than 400 hostages. On 18 May, when Yusuf learned of the insurrection to the villages of Chalkidiki, he ordered half of his hostages to be slaughtered before his eyes. The mulla of Thessaloniki, Hayrıülah, gives the following description of Yusuf's retaliations: "Every day and every night you hear nothing in the streets of Thessaloniki but shouting and moaning. It seems that Yusuf Bey, the Yeniceri Agasi, the Subaşı, the hocas and the ulemas have all gone raving mad." It would take until the end of the century for the city's Greek community to recover. Thessaloniki was also a Janissary stronghold where novice Janissaries were trained. In June 1826, regular Ottoman soldiers attacked and destroyed the Janissary base in Thessaloniki while also killing over 10,000 Janissaries, an event known as The Auspicious Incident in Ottoman history. In 1870–1917, driven by economic growth, the city's population expanded by 70%, reaching 135,000 in 1917. The last few decades of Ottoman control over the city were an era of revival, particularly in terms of the city's infrastructure. It was at that time that the Ottoman administration of the city acquired an "official" face with the creation of the Government House while a number of new public buildings were built in the eclectic style in order to project the European face both of Thessaloniki and the Ottoman Empire. The city walls were torn down between 1869 and 1889, efforts for a planned expansion of the city are evident as early as 1879, the first tram service started in 1888 and the city streets were illuminated with electric lamp posts in 1908. In 1888, the Oriental Railway connected Thessaloniki to Central Europe via rail through Belgrade and to Monastir in 1893, while the Thessaloniki-Istanbul Junction Railway connected it to Constantinople in 1896. 20th century and beyond In the early 20th century, Thessaloniki was in the centre of radical activities by various groups; the Internal Macedonian Revolutionary Organization, founded in 1897, and the Greek Macedonian Committee, founded in 1903. In 1903, an anarchist group known as the Boatmen of Thessaloniki