EL-ARISH, Egypt - Egypt has formed a military commission to investigate ways to destroy smuggling tunnels under its border with Gaza, a security official said Thursday.

A team of Egyptian engineers, border guards and intelligence officers arrived at the border area early Thursday morning with equipment to demolish the tunnels, a Ma'an correspondent said.

The security official told Ma'an there were over 1,200 tunnels under the border.

In the past, smuggling tunnels have been destroyed by filling them with cement or water or by using explosives.

Food, fuel and building materials are smuggled into Gaza through the tunnels, easing the tight blockade imposed by Israel since 2007.

Hamas ordered the sealing of the tunnels on Sunday after militants killed 16 Egyptian officers in an attack on a police station near the border in Sinai.

"Eighty percent of food materials in the markets of Gaza come from Egypt. What comes from Israel is not enough at all," said tunnel owner Abu Awni.

Long lines built at petrol stations across Gaza on Monday as news broke that the tunnels were blocked. Two days later some pumps had already run dry, even though Palestinians said at least two fuel pipes to Egypt were still functioning.

But Abu Awni predicted that the Egyptians would not be able to close the tunnels for long.

"Unless they create other crossings for trade, we will open five tunnels for each tunnel they close. They cannot just leave our people to starve," he said.

An Egyptian military offensive on the Sinai peninsula entered its second day on Thursday after gunman fired shots towards a police station in the main administrative center of North Sinai on Thursday.

Hundreds of troops in armored cars drove out of el-Arish to hunt Islamist militants blamed for Sunday's attack.

Residents in el-Arish welcomed the security sweep, seeing it as an opportunity to curb criminality among Bedouin tribes, including those in Sheikh Zuwaid, who make their living smuggling goods and people through the network of tunnels into Gaza.

"We want the army to return to the border," said 45-year-old shopkeeper Hassan Mohamed. "The tunnels have destroyed the lives of people in el-Arish. We want them to hit the Bedouin hard."