CAIRO — Gunmen in Egypt’s Sinai peninsula opened fire on Israeli troops across the border on Wednesday, wounding two soldiers, the Israeli military said.

Islamist militants are active in the lawless peninsula, which borders southern Israel, though assaults across that boundary are rare.

The attackers fired guns and an anti-tank missile at the Israelis, the military said in a statement.

Security concerns and an influx of tens of thousands of African migrants prompted Israel to erect a 250 km (160 mile) long barrier from the Red Sea port of Eilat to the Palestinian Gaza Strip on the Mediterranean. It was completed in 2012.

Earlier that year, attacks by militants operating from Sinai killed an Israeli soldier and a civilian who were working on the frontier fence.

Israel and Egypt signed a peace treaty in 1979 and Egyptian forces have been trying to curtail Islamist militant operations in Sinai. Wednesday’s attack occurred about half way between Eilat and the Gaza Strip.