Egyptian military troops and jets killed 20 terrorists in the Sinai region bordering Israel on Wednesday, striking back after armed men attacked several security checkpoints, an army commander in Sinai told Reuters. "We have succeeded in entering al-Toumah village, killed 20 terrorists and destroyed three armored cars belonging to terrorists. Operations are still ongoing," he told Reuters. Related stories: Egypt had early warning on Sinai attack Egypt sends helicopter gunships to Sinai Egypt buries soldiers slain in border attack Security officials say it is the first time that the army has fired missiles in Sinai since Egypt's 1973 war with Israel, which was an attempt to recapture the Sinai Peninsula. The military offensive follows attacks on Sunday that killed 16 border guards and which the government blamed partly on Islamist militants. The commander said the army had received information that many militants were in al-Toumah village. Officials say six people were wounded in the attacks - among them a military officer, two soldiers, two policemen and a civilian whose condition is critical. Security officials said the military also carried out separate attacks just outside Sheikh Zuwayed. Witnesses in Sheikh Zuwayed, about 10 km (six miles) from Gaza, said they saw two military jets and heard sounds of explosions. Other witnesses in a nearby area said they saw three cars hit. Egypt's Morsi visits Al-Arish on Monday (Photo: AFP) Egyptian media are reporting that the terrorists responded to the attack by firing anti-aircraft missiles at one of the apache helicopters, which eventually left the scene having escaped several downing attempts. Meanwhile, eye witnesses told The Guardian and Arabic-language Sky News that several fighter jets are taking part in the assault. Other reports said that the attack involves four fighter jets, 30 armored vehicles and dozens of Egyptian troops The strikes follow clashes between armed men and security forces at several security checkpoints in the Sinai region. Armed men opened fire on several checkpoints in Arish and in the nearby town of Rafah on the border with Israel, according to a Reuters reporter and state media. Funeral of Egyptian border guards killed on Sunday (Photo: AFP) An army officer, a police official and an officer were injured in the clashes. The Egyptian Interior Ministry announced that the army traced the gunmen's hiding places with the help of Sinai residents. Lawlessness in the rugged desert region bordering Israel has spread since the fall of autocratic leader Hosni Mubarak in an uprising 18 months ago and the election of an Islamist successor whose commitment to security cooperation with the Jewish state has yet to be tested. One of the checkpoints attacked on Wednesday has been attacked 28 times since the uprising, the state-funded Middle East News Agency said. Protesters demand state protection A few hours after the eruption of the clashes, hundreds of protesters gathered in Arish demanding state protection and chanting "God is Great." Security forces closed Arish's main highway shortly after the start of the attacks. Earlier on Tuesday, crowds of angry mourners wept at the military funeral in Cairo of the 16 guards killed in what was the deadliest assault in decades along Egypt's tense Sinai Peninsula border with Israel and Gaza. In reaction to Sunday's attacks, Egypt began to seal off smuggling tunnels into the Gaza Strip, a security source said. A Reuters reporter in Rafah said heavy equipment was brought to the Egyptian side of the tunnels, which are used to smuggle people to and from Gaza as well as scarce food and fuel for the small territory's population. Heightened alert in northern Sinai Also Wednesday, Egyptian newspaper Al-Shorouk reported that security forces in northern Sinai raised the alert level to the maximum with military and police armored vehicles patrolling the region. An emergency meeting of top security officials took place shortly before midnight in northern Sinai. The IDF had not been informed of the strikes but was not surprised by them. The operation was based on the agreed upon order of battle under the Israel-Egypt peace treaty. Meanwhile, the London-based al-Hayat newspaper quoted Egyptian sources as saying that Cairo officials have indetified the terrorists, some of whom are members of the al-Qaeda affiliated Army of Islam which operates in Gaza. Some of the terrorists wore explosive belts. The Mujahideen Shura Council of Jerusalem, which claimed responsibility for a June border attack which killed an Israeli, issued a statement denying involvement in the attack on the Egyptian army post. Reuters, AP, Roi Kais and Yoav Zitun contributed to this report Follow Ynetnews on Facebook and Twitter Receive Ynetnews updates directly to your desktop