Ahead of an expected full-blown invasion, Israel on Friday "expanded" its operations in the Gaza Strip and said that its air force conducted extensive strikes on Hamas' tunnels and other infrastructure.
In a televised news briefing, Israel's military spokesperson Rear Admiral Daniel Hagari said that their ground forces were expanding their operations, days after the Hamas members attacked Israeli towns and killed over 1,400 people.
"Following the series of strikes of the last days, the ground forces are extending the ground operations tonight," Daniel Hagari said late on Friday.
In a statement on Saturday, Israel said that its fighter jets struck 150 "underground targets" in northern Gaza during an intense night of raids.
The sites hit included terror tunnels, underground combat spaces, and additional underground infrastructure, the Israeli military statement said.
"Furthermore, several Hamas terrorists were killed", the statement added.
Following days of relentless bombing in retaliation to the surprise October 7 Hamas attack, Israeli troops had also made limited ground incursions on Wednesday and Thursday.
However, the extensive Hamas tunnel network, which is said to be hundreds of kilometers long and up to 80 meters deep, represents the greatest challenge to Israel. The Israeli forces are reportedly making "sponge bombs" to tackle this challenge.
What are "sponge bombs"?
Being called Israel's "new secret weapon", a "sponge bomb" is a kind of chemical grenade.
It contains no explosives but can be used to seal off gaps or tunnel entrances.
How do "sponge bombs" work?
As per reports, the "sponge bombs" are encased within a protective plastic container, which has a metal barrier that divides two distinct liquids.
Once activated, these liquids merge and advance toward their intended destination.
Earlier in 2021, the Israel Defense Forces (IDF) reportedly deployed these devices during exercises in a mock tunnel system near the Gaza border.