Israel army says flooding Gaza tunnels to halt Hamas attacks

The Israeli army said on Tuesday it is channelling water into Gaza's tunnels in a bid to destroy the sprawling underground network used by Hamas militants to launch attacks on Israel.

"It is part of a range of tools deployed by the [Israeli army] to neutralise the threat of Hamas's subterranean network of tunnels," the military said in a statement, confirming media reports.

Dubbed "the Gaza metro" by the Israeli army, there were 1,300 tunnels over 500 kilometres (310 miles) in Gaza at the start of the war in October, according to a study from US military academy West Point.

The military said it would destroy them in the wake of Hamas's 7 October attack in southern Israel, which saw some 250 captives taken to Gaza, of which around 132 are still held, including bodies of at least 28 people believed to have been killed.

The Israeli army says that many hostages taken by Hamas have been or continue to be held in the vast network of tunnels.

Israel has launched a brutal war on Gaza that has killed at least 26,751 people, mostly women and children, according to Gaza's health ministry.

In December some Israeli media reported the military was leaning towards flooding the tunnels with seawater pumped from the Mediterranean.

But experts warned the option was dangerous and posed huge risks to Gaza's besieged civilians.

"It will cause severe damage to the already fragile water and sewage infrastructure that's in Gaza," the then UN humanitarian coordinator for Palestinian territories, Lynn Hastings, had warned in December.

"There's even a risk to buildings and roads collapsing because of the increased pressure and infiltration of seawater into Gaza."

On Tuesday the army said it had taken care in a way as to not "damage the area's groundwater".

"The pumping of water was only carried out in tunnel routes and locations that were suitable, matching the method of operation to each case," it said.

"This tool is one of a range of capabilities developed by the [Israeli forces] and Israel's security establishment in recent years in order to operate against Hamas' underground infrastructure in the Gaza Strip."

The maze of tunnels was initially used to bypass Israel's devastating blockade on the Gaza Strip after Hamas came to power in 2007, allowing the smuggling of people and goods in and out of Egypt.