Israel’s ground invasion of Gaza commenced after 13 Hamas gunmen entered Israeli territory via an underground tunnel early Thursday, reports the New York Times. The attack, which targeted a kibbutz near the Israel-Gaza border, was thwarted by the Israeli air force.

Only a day later, the Israeli military stated that it had already discovered 10 tunnels with 22 exits throughout Gaza. It described the tunnels, which cross the Gaza-Israel border as “complex and advanced,” constructed with the intention to “carry out attacks such as abductions…infiltrations… [and] mass murders.” Other tunnels lead from homes in Gaza to concealed weapon storages. 

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Gadi Shamni, a former commander of the Israeli army’s Gaza division said that destroying the tunnels would be technologically and operationally challenging because of each tunnel’s many multidirectional offshoots. 

Gilad Shalit, the Israeli soldier captured and held by Hamas for five years, was taken away to Gaza in one of such tunnels.  

Hamas has repeatedly boasted that it has “surprises” in store for Israel, presumably referring to the tunnel network. It released a propaganda video on Thursday depicting its special forces attacking a mock village similar to those found on Israeli military bases. 

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