Jerusalem | The Israeli military said on Wednesday that it has reopened the Kerem Shalom crossing into Gaza, a key terminal for the entry of humanitarian aid that was closed nearly three days earlier after a Hamas rocket attack killed four Israeli soldiers nearby.

An Israeli tank brigade seized the nearby Rafah crossing between Gaza and Egypt early Tuesday, and it remained closed.

Associated Press journalists heard sporadic explosions and gunfire in the area overnight, including two large blasts early Wednesday.

Rafah has been a vital conduit for humanitarian aid since the start of the war and is the only place where people can enter and exit. Israel now controls all of Gaza's border crossings for the first time since it withdrew troops and settlers from the territory nearly two decades ago.

Gaza's Health Ministry says at least 46 patients and wounded people who had been scheduled to leave for medical treatment have been left stranded.

UN agencies and aid groups have ramped up humanitarian assistance in recent weeks as Israel has lifted some restrictions and opened an additional crossing in the north under pressure from the United States, its closest ally. But aid workers say the closure of Rafah, which is the only gateway for the entry of fuel for trucks and generators, could have severe repercussions.

The UN says northern Gaza is already in a state of “full-blown famine”.

The operation to capture the crossing appears to have been a limited incursion and not the start of the massive invasion of Rafah that Israel has promised. But Israel has said it will expand the operation if ongoing indirect talks with Hamas over a cease-fire and hostage release fail to make progress.