Thousands of Israeli forces, accompanied by bulldozers, spread out across the settlements in the occupied strip, marching through barricades at first light after a midnight deadline expired for settlers to leave willingly.
“We have reached the stage now where the disengagement will be enforced,” said an army spokesman, speaking to AFP.
“[Troops] are there to enforce the disengagement law.”
A first busload of Israelis arrived at the Kissufim crossing after being expelled, and hurled abuse at soldiers manning the border.
Witnesses at Nissanit, in the northern Gaza Strip, report that forces have started demolishing buildings vacated by departing settlers hours after electricity was cut off, according to a Reuters report.
An army spokesman has indicated the evacuation operation should be completed within a few days.
There have been many reports of settlers screaming abuse and resisting police and soldiers’ attempts to remove them, amid smoke from blazing tyres, lit in an attempt to thwart evacuations.
In Neve Dekalim, around 50 troops dragged nine elderly women away kicking and screaming on to a bus.
Witnesses said there were scenes of chaos at the settlement, which has seen violent clashes in recent days, as security forces loaded youths on to a bus.
At one stage, one of the youths smashed a window on the vehicle, clambering out of the back before being intercepted, according to AFP.
Thousands of hardline Jews and opponents of the plan have managed to get past barriers into Gaza to support the settlers, some of them barricading themselves behind trenches and barbed wire.
A steady stream of sobbing people left the Gaza Strip in buses and cars laden with possessions on Tuesday, many overcome with anguish.
“I feel like I’m on the way to Auschwitz. Shame on you!” screamed one young girl.
Hundreds, even thousands, of settlers defied a midnight deadline to leave willingly, and will now be forced from their homes.
Around 10,000 soldiers and police are expected to take part in the Neve Dekalim operation, the main focus of the historic pullout.
It is the first time Israel has withdrawn from Palestinian territory captured in the 1967 Arab-Israeli war, and has raised hopes in the international community of a new breakthrough in Middle East peace.
All 21 Jewish settlements in the Gaza Strip will be dismantled.