Islamic State urged insurgents in Egypt's Sinai Peninsula on Monday to press ahead with attacks against Egyptian security forces and beheadings, a call likely to deepen concern over ties between the militant groups.
Egyptian officials, including the foreign minister, have acknowledged coordination exists between Islamic State and other militant groups, including ones in Egypt, but have said there are no Islamic State fighters in the country.
Egypt has faced Islamist insurgents since the army toppled President Mohamed Morsy of the Muslim Brotherhood last year.
"Rig the roads with explosives for them. Attack their bases. Raid their homes. Cut off their heads. Do not let them feel secure," Islamic State spokesman Abu Muhammad al-Adnani said in a statement to Egyptian militants released online.
He praised those militants for carrying out "blessed operations against the guards of the Jews, the soldiers of Sisi, the new Pharaoh of Egypt" - a reference to Egyptian President Abdel Fattah al-Sisi who succeeded Morsy.
Sinai-based militant group Ansar Bayt al-Maqdis, which has killed hundreds of Egyptian security forces over the last year, beheaded several people in recent weeks, saying they were spies for Israeli intelligence.
The bloodshed, the first of its kind in the biggest Arab country, suggested the group, which seeks to remove the US-backed government, had become more radical.
Sisi, who as army chief last year led Morsy's ouster following protests against his rule, has expressed concerns about Islamist militants in Egypt and the Middle East.
Egypt has backed Washington's call for global action to counter the threat from Islamic State.
But Foreign Minister Sameh Shokry suggested Cairo might not provide direct military assistance to the United States for its battle against the group, saying the army was focused on the home front.
The challenge of containing militancy has become more complex since Islamic State militants expanded their control over northern Iraq and eastern Syria in June and declared a caliphate, inspiring other militant groups including some based along Egypt's border with chaotic Libya.
Containment
Islamic State, made up of Iraqis, other Arabs and foreign fighters, has been coaching the Sinai-based Ansar militants on how to operate more effectively, a senior Ansar commander told Reuters this month.
Egyptian security forces had appeared to be making some progress against Islamist insurgents over recent weeks. The Ansar commander said pressure from the army had forced some fighters to flee the Sinai for other areas in Egypt.
On Sunday, a bomb attack beside the Egyptian foreign ministry in Cairo claimed by militant group Ajnad Misr (Soldiers of Egypt) killed three policemen, including a key witness in a trial of Morsy.
The European Union condemned the blast, calling it a "heinous act".
Egypt has branded the Muslim Brotherhood a terrorist group and pledged to eliminate it after security forces killed hundreds of its supporters, arrested thousands and put top leaders on trial, severely weakening what was once Egypt's most organized political group.
The Brotherhood says it is committed to peaceful activism, but authorities make no distinction between Islamists, blaming them all for violence which has hammered tourism, a pillar of the economy.
Despite several army operations Egypt's military has struggled to tackle Ansar, Ajnad and other militant groups.
The Egyptian state has crushed militant groups in the past but they often recover. In the 1990s, militants staged attacks against government officials and foreign tourists. It took then President Hosni Mubarak years to defeat them.
