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I found a documentary from 2008 about smuggler tunnels in Gaza. Child labor to smuggle 'luxury' goods over to make some money. Also weapon smuggling no doubt.
Inside the Gaza Tunnels: Children digging for Hamas? | 2008 | ENDEVR Documentary
Most of Hamas' weapons are smuggled into Gaza through tunnels from Egypt. These tunnels are at the heart of the conflict with Israel.
Children usually dig these tunnels, aware they are in constant danger. Every night, 14-year-old Said scrambles down a narrow shaft leading to a tunnel. He'll spend the next eight hours digging without a break. It's claustrophobic, difficult work. The heat in the tunnel is unbearable and the more they advance, the harder it becomes to breathe. At any moment, the tunnel could come crashing down, burying them alive.
That's not the only danger. "Sometimes the Egyptians shoot gas into the tunnel that might kill us", states Ramdan. "There are risks of electric shocks and the Israelis might bomb the entrance". Since Hamas seized control of Gaza, the borders have been closed. The tunnels are the only way to import goods into the territory. "They're a gold mine!" states Said. But to his disgust, most of the profits go to other people. "We do all the work, then they swindle us", he complains. Once the tunnel is nearly ready, "other people will open it, do the trafficking and make more money than us". The money he does make will enable Said to support his entire family. But every time he goes into the tunnel, he knows: "You are digging your own grave".
The IDF left Gaza in 2005, but the siege never lifted. Israel imposed a total blockade on Gaza in 2007 after Hamas was elected in power. (Supported by Netanyahu to drive a wedge between Fatah's control of the West Bank and Gaza)
Later on in the documentary they also talk about the Philadelphi line, basically cutting part of Rafah of that it's still in Egypt today.
What the Rafah border looked like in 2008
High school children digging tunnels to their friend's houses across the border to smuggle goods to make money for their family as there was/is little work in Gaza. They show how they used Google Earth to plot their routes.
Hamas of course knew about all this, profited of this and also used the tunnels to smuggle weapons.
These tunnels have since been destroyed by Egypt
Egypt has destroyed more than 2,000 Gaza tunnels, secret files reveal
https://www.middleeasteye.net/news/egypt-army-leak-destruction-gaza-tunnels-rafah
2013 Egypt destroys smuggling tunnels on Gaza border
https://www.timesofisrael.com/egypt-destroys-smuggling-tunnels-on-gaza-border/
2015 As Egypt Floods Gaza Tunnels, Smugglers Fear an End to Their Trade
https://www.nytimes.com/2015/10/08/world/middleeast/as-egypt-floods-gaza-tunnels-smugglers-fear-an-end-to-their-trade.html
Floods and bombs: This is how Egypt handled Hamas' smuggling tunnels
https://www.israelhayom.com/2023/10/22/floods-and-bombs-this-is-how-egypt-handled-hamas-smuggling-tunnels/
The IDF dug up some of the old tunnel entrances in Rafah trying to insinuate smuggling was still going on. I wouldn't rule it out, where there's money to be made, people find a way. But there's no recent information about smuggling or children digging tunnels.
