Gaza, Oct 21 : The first convoy of trucks loaded with humanitarian aid entered Gaza on Saturday through the Rafah crossing, the only crossing point between the besieged Hamas-controlled enclave and Egypt, according to Palestinian security sources. It remains unclear till when the crossing will remain open, but Israel has so far agreed to allow 20 trucks into Gaza, reports the BBC. Earlier in the day, the US embassy in Israel said that it had received information that the Rafah crossing will open at 10 a.m. (local time) on Saturday morning. 'If the border is opened, we do not know how long it will remain open for foreign citizens to depart Gaza. We anticipate that many people would attempt to cross should the border open," CNN quoted the mission as saying 'US citizens attempting to enter Egypt should expect a potentially chaotic and disorderly environment on both sides of the crossing." The Embassy added that the situation remains 'dynamic and fluid,' and the security environment is 'unpredictable,' advising people to 'assess your personal safety and security before choosing to move toward the border or trying to cross.' Humanitarian aid has been stuck in Egypt for days as Gaza plunges into a worsening humanitarian crisis amid the raging Israel-Hamas conflict. Gaza is fast running out of food, water, fuel and medical supplies, while electricity blackout and ban on fuel imports have had 'devastating consequences' on the healthcare system and access to clean water, the UN's Office for the Coordination of Humanitarian Affairs (OCHA) warned on Saturday. It added that about 1.4 million people had been displaced in Gaza ' more than 60 per cent of the entire strip's population of 2 million. /IANS