Egyptian facebook news network RNN reported on its page that big Egyptian military bulldozers started the demolition of the tunnels. They were protected by military vehicles.
Eyewitnesses from Rafah, Gaza's southern city which is adjacent to Egypt, said that they had seen the bulldozers at work; that they had seen them arrive several days ago, but that they had only started working today.
They said that heavy automatic guns are mounted on the military vehicles protecting the bulldozers there.
Egyptian sources said that new military forces arrived in the area between Egypt and Gaza yesterday [Wednesday].
The smuggling of commodities to the Gaza Strip was halted several days before the start of the unrest in Egypt.
Palestinian security forces raised the alert on the tunnels fearing chaos might occur during the unrest.
Tunnels between Egypt and Gaza have been the main life line to the 1.8million residents of Gaza since the Israeli siege was imposed in 2006.
The siege, which was imposed following Hamas' shock victory in the Palestinian parliamentarian elections, is internationally agreed upon.
The ministry of health in Gaza announced that fuel for electricity generators and ambulances will run out within days. "We are facing an unknown future with the closure of the tunnels," a statement said.
Israel does not allow enough fuel through its crossings with Gaza.