Israel has moved blocks marking its post-ceasefire Yellow Line deeper into Gaza at several points, satellite images reviewed by BBC Verify show. In at least three areas — Beit Lahia, Jabalia, and al-Tuffah — the Israel Defense Forces (IDF) placed concrete yellow blocks and later moved them further inside Gaza. Sixteen positions in total were repositioned. The blocks mark the line Israel agreed to withdraw beyond as part of a US-brokered deal with Hamas. Defence Minister Israel Katz warned in October that crossing the Yellow Line would be met with fire. Since then, deadly incidents near this line have increased. Satellite pictures from 27 November to 25 December show seven blocks in al-Tuffah moved an average of 295 meters deeper into Gaza. More than half of 205 other markers mapped were also placed farther inside Gaza than on official maps. The IDF denies moving the Yellow Line positions and says it places blocks based on operational needs and ground conditions. However, around 10 km of the Yellow Line remain unmarked on the ground, leaving many Gazans unsure where this "dangerous combat zone" begins. A 23-year-old man living near Khan Younis told the BBC, "We are now living inside the Yellow Line, [but] behind the yellow blocks, with no idea what our fate will be." He described terrifying nights with constant shelling, gunfire, and drone noise. Experts warn that shifting the blocks could be a way for Israel to control where Gazans live and move without officially changing borders. Since Katz's warning, troops have fired at people crossing the line at least 69 times. On 19 December, an IDF strike hit a school sheltering displaced people near moved blocks, killing five including children. The IDF said it fired on "suspicious individuals" and regrets harm to uninvolved people. Another incident involved a 17-year-old in Jabalia who was shot and run over by a tank near the Yellow Line. The army says Hamas fighters fired on troops beyond the line at least six times last week. Despite the ceasefire agreement to stay behind the Yellow Line, videos and satellite images show Israeli forces operating beyond it, with tanks and bulldozers seen hundreds of meters inside Gaza. Buildings near some moved blocks have been demolished, sometimes hiding the markers. The IDF says it is dismantling Hamas tunnels under buildings, which may cause collapses. The U.S. announced that the ceasefire's second phase will begin soon, involving more Israeli withdrawal linked to Hamas demilitarization. Meanwhile, Israel has built temporary fortifications beyond the mapped line, stirring fears the area could become a "sterilised belt." The true border on the ground seems to shift with the movement of these concrete blocks.