Hamas is determined to go through with its threat to forcefully breach the border between the Gaza Strip and Egypt in the coming days, a senior Israeli defense official said Wednesday. Egyptian troops went on high alert near the Rafah crossing after the threat was made. Egypt's Foreign Ministry warned Gazans that any attempts to "infringe upon the Egyptian borders will be met with a serious and firm position." On January 23, Hamas blew holes in the border wall, allowing hundreds of thousands of Palestinians to stream into Egypt unchecked for 12 days and stock up on food and other goods made scarce due to Israeli sanctions on the flow of supplies into Gaza in the wake of daily Kassam rocket attacks from the Strip. Hamas smuggled truckloads of explosives and weaponry into Gaza while the border was open, security officials said. The Israeli defense official said that Hamas might blow up the border wall early on Thursday morning. The official said Hamas's plans might be delayed due to Wednesday's attack at the Nahal Oz fuel depot in which terrorists shot two Israelis dead. "They have most likely already planted explosives along the border with Egypt," the official said. Egyptian officials said that about a thousand troops were put on high alert near Gaza after Egypt received intelligence that Hamas was preparing to bulldoze the rebuilt border and to blow up the main crossing gate with mines. On Tuesday, Hamas lawmaker Khalil al-Haya described the situation in Gaza as "no longer bearable" and renewed threats to breach the border again. The Egyptian Foreign Ministry warned that any move to do so would hurt the Palestinian cause and undermine efforts to end the Israeli embargo on Gaza. The ministry statement criticized the timing of the Hamas threats, saying they coincided with "the concocted problems inside Egypt," an apparent reference to this week's deadly riots over rising food prices. Egyptian police also said they discovered a large cache of explosives and weaponry along the border with Gaza. The large underground chamber showed signs of long-term use and contained 1,250 kg. of explosives, 24 anti-tank mines and assault rifles. Police found the cache in the remote mountainous Hadhira area with the aid of Beduin trackers who are now scouring the area for suspects, the security official said. AP contributed to this report.