Pope Francis on Sunday pledged to follow up reforms in the Church, despite what he called "deplorable" leaks revealing his fury over uncontrolled spending by the Vatican.

"I want to assure you that this sad fact will not prevent me from the reforms which will proceed with my collaborators and the backing of you all," he said after Angelus prayers.

Fierce clashes have erupted between two rival Taliban groups in southern Afghanistan, officials said Sunday, reportedly leaving dozens dead in the first internecine fighting since a breakaway faction of the Islamist movement appointed its own leader.

The skirmish was taking place in southern Zabul province between fighters loyal to the widely-recognized Taliban leader Mullah Akhtar Mansour and followers of Mansoor Dadullah, a deputy of splinter-group leader Mohamed Rasool who announced his own faction Tuesday.

Rwandan President Paul Kagame has accused Burundi's leaders of carrying out "massacres" on their people in his most critical speech yet of the crisis in the troubled neighboring state.

"People die every day, corpses litter the streets... How can the leaders allow their population to be massacred from morning to night?" Kagame said, speaking in Kinyarwanda on Friday, in a speech heard by AFP on Sunday.

Saint Petersburg on Sunday remembered the victims of the Sinai plane crash, with the bell of the iconic St. Isaac's Cathedral tolling 224 times in memory of each person killed.

At an emotional memorial service at one of the former imperial capital's most famous symbols, a chamber choir sang as several hundred mourners looked on.

Stranded in the Egyptian resort of Sharm el-Sheikh, British tourist Joanna Baker is growing increasingly frustrated despite her luxurious surroundings.

Baker and her boyfriend were scheduled to fly out Friday after a week of holidays in the Red Sea town, but instead are stuck like thousands of fellow holidaymakers after Britain suspended flights to Sharm el-Sheikh over last week's crash of a Russian airliner.

In the poverty-stricken far north of Cameroon, the priority is the fight against the Nigerian militants of Boko Haram, but experts say a growing humanitarian crisis also needs urgent attention.

Chased from their strongholds in northeast Nigeria by a multi-national army offensive, the insurgents of Boko Haram have increased the tempo of suicide attacks and bloody raids on neighboring Cameroon despite the deployment of a huge military contingent along the border.

Two powerful quakes struck Indonesia's Sumatra on Sunday, U.S. seismologists said, but no tsunami warning was issued and there were no immediate reports of damage or casualties.

An initial 6.1-magnitude undersea tremor struck at a depth of 75 kilometers (47 miles) in the afternoon, the U.S. Geological Survey (USGS) said.

A twin suicide bombing by women attackers in the flashpoint area of Lake Chad on Sunday killed two people and wounded 14 others, a security source in the Chadian capital N'Djamena said.

"The two women suicide bombers and two civilians died in the blast," the source told AFP on condition of anonymity, adding that "14 others were injured" in the attack blamed on Nigeria's Boko Haram group on Ngouboua village near the Nigerian border.

A Somali member of parliament has died hours after he was shot and wounded when gunmen sprayed his car with bullets, the prime minster said Sunday.

MP Mohamed Ahmed Gurhan was hit by gunfire several times as he traveled through the capital Mogadishu on the way to parliament on Saturday, the latest attack targeting members of parliament.

Moscow and London ramped up efforts Sunday to bring home thousands of tourists stranded in Egypt's Sharm el-Sheikh resort following the crash of a Russian airliner in the Sinai Peninsula.

Britain and the United States, as well as international investigators, suspect a bomb exploded on board the Russian Airbus after it took off from the Red Sea resort last Saturday en route to Saint Petersburg, killing all 224 people on board.