Two Israeli soldiers were wounded Wednesday when alleged drug smugglers fired shots and an anti-tank missile from Egypt's Sinai Peninsula at their vehicle patrolling the border, the army said.
Troops responded to the attack, near the border community of Ezuz about 60 kilometres (37 miles) south of the Gaza Strip, killing three of the assailants.
"About 2:00 pm (1100 GMT), we had shots and an anti-tank missile fired at a vehicle that was on the border," said army spokesman Lieutenant Colonel Peter Lerner.
Two soldiers on patrol suffered light-to-medium injuries, he said.
They were a female officer and a male soldier from the predominantly female Caracal battalion responsible for defending the border.
Lerner later tweeted that an investigation had shown the attack was a "violent drug smuggling attempt, foiled by Caracal Company Commander."
An army statement said "the shots came from three different positions, including a car that drove along the border, and the military responded, killing at least three of the attackers."
Egyptian security officials confirmed gunmen had opened fire on the Israeli patrol, saying they believed the assailants had earlier clashed with Egyptian soldiers.
The Sinai Peninsula has seen a significant increase in attacks by militants targeting Egyptian security forces and the Israeli border after the army overthrew Islamist president Mohamed Morsi in July last year.