Jerusalem (AFP) - Israel's military said Wednesday it had arrested the brother of a Hamas security chief accused of involvement in tunnel building in the Gaza Strip.
The military said in a statement that Bilaal Razayna, 24, was arrested after crossing from Gaza into Israel, while the Shin Bet domestic security service said he had crossed the security fence.
His brother Mustafa Razayna is a head of internal security in the northern Gaza Strip for Hamas, the Islamist movement that runs the Palestinian enclave, according to the Shin Bet.
Gaza interior ministry spokesman Iyad al-Bozum said the man arrested had been detained when approaching the border on the Gazan side of the fence.
He said his brother worked in the interior ministry, without providing further details, but added that the man had mental health problems and was not in contact with the Gaza security services.
The military said Razayna was arrested on November 27, but the information was cleared for release only on Wednesday.
It alleged he was part of Hamas's armed wing, the Ezzedine al-Qassam Brigades, for the past 10 years and "was closely associated with the tunnel network in the Gaza Strip".
"Razayna revealed sensitive information regarding Hamas activity, including that part of the tunnel system within the Gaza Strip was constructed under his home, which was also used as a weapon storage facility," the military statement said.
The Shin Bet said he had been charged with membership and activity in a banned organisation and weapons offences.
Over the years, Hamas has built a labyrinth of tunnels, including those crossing under the border with Israel, for use in any renewed conflict.
Israel and Palestinian militants in Gaza have fought three wars since 2008, and the territory has been under an Israeli blockade for a decade. Gaza's border with Egypt has also remained largely closed.
Tunnels were a key weapon for Hamas during the last conflict in 2014, and were used to stage a number of surprise attacks inside Israeli territory.