Three Palestinians missing in Egypt-Gaza tunnel in 'mysterious circumstances'

Three Palestinians have gone missing from a tunnel between Egypt and the beseiged Gaza Strip in mysterious circumstances, Hamas authorities said on Monday.

"Three Palestinian workers disappeared inside one of the tunnels on the Palestinian-Egyptian border and the security forces are investigating to locate their whereabouts," the Hamas-run interior ministry in Gaza City said in a statement.

A number of Gazans have died in tunnel collapses in recent months, but there were no reports of such incidents on Monday.

One witness told AFP that a group of masked gunmen snatched the three and took them across the border into Egypt's Sinai Peninsula.

The account of the witness, who spoke on condition of anonymity, was not confirmed by authorities.

Egyptian security forces have been fighting a branch of the Islamic State (IS) group in the Sinai, and the extremists have recently stepped up their attacks.

In August, a suicide bomber killed a Hamas guard along Gaza's border with Egypt in what was described as a rare Islamist attack against the Palestinian group.

In 2015, gunmen seized four Hamas members from a bus bound for Cairo from the Gaza Strip in the Sinai near the border.

Egypt has cracked down on tunnel crossings from Gaza into the Sinai, and Hamas has agreed to improve security along the border.

Tunnels between Gaza and Egypt are typically used for smuggling.

The Gaza Strip has been under an Israeli blockade for more than a decade, while Egypt has also kept its border with the Palestinian enclave largely closed in recent years.

Hamas and Israel have fought three wars since 2008.