EL-ARISH, Egypt – Egypt deployed helicopter gunships to the Sinai Peninsula Monday to hunt for the militants who killed 16 soldiers near the border with Israel before crossing into the Jewish state in an armored vehicle. Israel said five gunmen were killed on its side of the border late Sunday. Gunmen in Bedouin attire drove up to the checkpoint and opened fire, Egyptian officials said. Israel said two armored vehicles were seized, one of which exploded by itself and the other of which was destroyed by a helicopter. Israel stepped up pressure on Egypt to clamp down on the lawless border zone. Egyptian President Mohamed Morsi had vowed to retake control of the Sinai after the attack, saying he had given “clear instructions” that Egypt must take “full control of the Sinai” after the security situation deteriorated markedly following last year's ouster of long-time strongman Hosni Mubarak. Morsi said those who committed the “cowardly” attack and those who worked with them would pay dearly. “Those responsible for this crime will be hunted down and arrested,” he said. “Everybody will see that the Egyptian military and police forces can get these criminals wherever they are,” he said. “These criminals, these attackers do not belong among us.” State television and MENA reported that Egypt was closing its Rafah frontier crossing with the Hamas-controlled Gaza Strip “until further notice.” Rafah is the only crossing between Gaza and the outside world that is not under Israeli control. MENA called the gunmen “jihadist elements” who “infiltrated from Gaza through tunnels in collaboration with jihadist elements in the Al-Mahdiya and Gabal Halal areas” inside Egypt. They “attacked a border post while the soldiers and officers were taking iftar,” it added. Earlier Sunday, before MENA's report, Hamas in Gaza had dismissed the idea that militants from the Palestinian territory may have been involved. A Hamas statement said: “We condemn this ugly crime in which Egyptian soldiers were killed, and send our condolences to the families of the victims, and to the Egyptian leadership and the Egyptian people.” Hamas said Monday that its security forces in the Gaza Strip are on the alert after Egypt's army vowed to avenge the killing of 16 guards by gunmen near the Israeli border. “The national security services are on a 100-percent state of alert to maintain common security between the Gaza Strip and Egypt,” Jamal Al-Jarrah, head of the Hamas security forces, wrote on the interior ministry website. He accused Israel of encouraging speculation that Gaza Palestinians were involved in Sunday's attack. “The occupation is trying to spread its rumors and hold Gaza responsible for the attack, to cause tension in relations between the Palestinian and Egyptian peoples,” said Jarrah. “We assert that we are working around the clock to maintain common security.”– Agencies