This article is more than
8 year oldA statement said the tunnel had been constructed by the Palestinian militant group Hamas "in order to infiltrate Israel and execute terror attacks".
Hamas, which dominates Gaza, said Israel had found an "old" tunnel.
It is the first such tunnel to be found since the devastating war between Israel and militants in Gaza in 2014.
During 50 days of fighting, Hamas fighters used tunnels to infiltrate Israeli territory on four occasions, killing 12 soldiers, while Israeli troops destroyed more than 30 tunnels.
The conflict left at least 2,251 Palestinians dead - including more than 1,462 civilians, according to the UN - and 11,231 injured. Some 18,000 homes in Gaza were also destroyed or badly damaged.
On the Israeli side, 67 soldiers and six civilians were killed, and up to 1,600 injured. Rockets and mortars launched f-rom Gaza caused damage to homes and other buildings inside Israel.
Following the war, the Israeli military said it was developing technology aimed at countering efforts by Hamas to rebuild its tunnel network.
The military statement issued on Monday said the "combined efforts of intelligence, technology and ground forces" had led to the latest discovery in southern Israel.
"The ugly truth is that Hamas continues to invest millions of dollars to build tunnels of terror and death," spokesman Lt Col Peter Lerner said.
"The tunnel uncovered in Israel demonstrates once more Hamas's warped priorities and continued commitment and investment in tools of violence."
Col Lerner said the tunnel was about 100-130ft (30-40 metres) deep and was found near the community of Sufa, about 3.5 miles (6km) f-rom Gaza.
He said the construction was new, lined with concrete, and fitted with an electricity supply, ventilation and rail tracks, but did not have an exit.
However, Hamas claimed that the Israeli military had announced "the finding of an old tunnel in order to gain continued US support for its anti-tunnels project".
The Hamas-affiliated website, al-Majd, reported that the tunnel had been used two years ago.
Earlier this month, Israel suspended deliveries of cement for private projects in Gaza, saying Hamas was diverting the material for its own purposes in violation of a UN-backed agreement following the 2014 war.
The Israeli military launched Operation Protective Edge in July 2014 with the stated aim of stopping rocket attacks by Hamas and destroying the group's capabilities to conduct operations against Israel.
After an initial phase focused on air strikes, the Israeli military launched a ground offensive that sought to degrade militants' infrastructure in Gaza and destroy their network of tunnels.
The operation concluded that August, when both sides agreed to a ceasefire.
Newer articles
<p>A US judge has ruled against Donald Trump getting his hush money conviction thrown out on immunity grounds.</p>