An Egyptian border guard was killed on Wednesday during a shootout with people traffickers trying to cross into Israel with illegal African migrants, a security official said.

Thousands of Eritreans and Sudanese nationals flee each year to Israel with the help of armed groups across a vast desert region stretching from Sudan, through Egypt and up to the Sinai Peninsula.

The United Arab Emirates and Egypt secretly bombed Islamist militia in Libya, apparently catching Washington off guard, as turmoil in the North African country deepened with the Islamists naming a rival premier.

The U.S. government said on Tuesday that the UAE and Egypt were behind last week's two deadly night raids on Islamist positions near Tripoli airport.

Egypt Tuesday denied any "direct" role in air raids on Islamist positions in Libya, after U.S. officials said the United Arab Emirates carried out the strikes from bases in Egypt.

"We have no direct tie to any military operation in Libya," Foreign Minister Sameh Shoukri told journalists in Cairo.

UAE air strikes on Libya aim to prevent Islamists from controlling the violence-stricken country and sends a message to Washington that it is capable of protecting its own interests, experts say.

United States officials said that United Arab Emirates warplanes secretly bombed Islamist militia targets in Libya from bases in Egypt last week, but Abu Dhabi has not publicly acknowledged involvement. On Tuesday, Egypt denied any "direct" role in the raids.

Nineteen people were killed and 15 injured when two minibuses plunged into an irrigation canal in southern Egypt early on Tuesday, a health ministry official said.

Sudan, Egypt and Ethiopia opened talks Monday to try to resolve a dispute over a hydro-electric dam being built by Addis Ababa on the Nile.

Cairo fears that Ethiopia's Grand Renaissance dam project could diminish its water supply.

Libya's neighbors Monday backed an Egyptian call for rival militias in the tumultuous North African country to be disarmed, agreeing with Cairo that there should be no foreign intervention to stem spiraling lawlessness.

Foreign ministers from Libya, Egypt, Algeria, Tunisia, Sudan and Chad met a day after Cairo denied Islamist militia accusations that it had conducted an air strike against Islamists in Tripoli.

Egypt on Monday is to host a meeting of foreign ministers of Libya and its neighbors, as Islamist militias openly challenge the legitimacy of parliament after seizing Tripoli's airport.

Almost three years after a NATO-backed revolt ousted strongman Moammar Gadhafi, Libya has been roiled by fighting between ex-rebels who have formed militias.

President Abdel Fattah al-Sisi on Sunday denied reports that the Egyptian air force carried out air strikes in Libya on Islamist militiamen around the capital's airport.

While they may be united in negotiations over a Gaza truce with Israel, rival Palestinian movements have not set aside historic disagreements which threaten to shatter their fragile alliance, experts say.