For every Ukraine protester smashing in a window, throwing a Molotov cocktail or being hit by riot police, there will be several people standing nearby with their smartphones aloft livestreaming the event.

Web channels have sprung up -- some with presenters in improvised studios commenting in real time on the live feeds from protests in Kiev and beyond -- and clips of some of the most shocking clashes have gone viral on social media.

An al-Qaida inspired group said it carried out the assassination on Tuesday of a top Egyptian police general and threatened similar attacks against the army chief and interior minister.

General Mohamed Saeed, an aide to interior minister Mohamed Ibrahim, was gunned down as he left his home in a west Cairo neighborhood on Tuesday morning.

Gunmen shot dead a policemen guarding a church in Cairo on Tuesday, and wounded two others, security sources said, hours after another attack claimed the life of a police general.

The shootings come a day after Egypt's military backed its chief Field Marshall Abdel Fattah al-Sisi, who led the ouster of Islamist president Mohammed Morsi, to run for the presidency.

Three years after a popular uprising forced out ex-general Hosni Mubarak, Egypt's army is again pushing a commander to stand for president after he ousted the first civilian head of state.

On Monday, the army endorsed its Field Marshall Abdel Fattah al-Sisi's candidacy for an election he is expected to win amid a strong nationalist fervor since he overthrew president Mohammed Morsi.

Ousted president Mohammed Morsi was defiant as he went on trial Tuesday for a prison break during the 2011 uprising, as a top police official was murdered in another sign of Egypt's instability.

The trial, and other violence in which a police guard was gunned down outside a Cairo church, came a day after the military backed army chief Field Marshall Abdel Fattah al-Sisi, who led Morsi's ouster in July, to run for office in his place.

Egypt's deposed president Mohamed Morsi went on trial Tuesday on charges of breaking out of prison during the 2011 uprising against veteran strongman Hosni Mubarak.

Morsi, ousted by the army in July, is already on trial for inciting the killings of opposition activists during his presidency and faces two other trials that have yet to begin.

Suspected militants blew up a pipeline in Egypt's Sinai that transports gas to Jordan late Monday in the third such attack in less than a month, security officials said.

The officials said there were no immediate reports of injuries, but witnesses said thick flames rose into the sky from the spot where the pipeline was struck.

U.S. officials on Monday deflected questions about plans for Egypt's army chief to run for the presidency, but stressed it was important to maintain "checks and balances" between the military and government.

"Only the people of Egypt can take the next steps in their transition," said White House spokesman Jay Carney as the Egyptian military backed its commander General Abdel Fattah al-Sisi to stand in presidential elections slated for mid-April.

Libya's prime minister said Monday five Egyptian diplomats kidnapped in Tripoli and freed as part of an apparent prisoner swap will return to their homeland "in a few hours".

Kidnappers snatched four Egyptian diplomats in Tripoli on Saturday, the day after another member of the embassy in the city was taken.

Progressive Socialist Party chief MP Walid Jumblat hailed on Monday former Prime Minister Saad Hariri's recent stands on local and regional developments.

He lauded to the PSP-affiliated al-Anbaa website the former premier's “refusal to drag the Sunni sect towards the conflict between Hizbullah and al-Qaida.”