Mats Hummels headed Germany to a 1-0 victory over old rivals France on Friday, and took his country to the World Cup semi-finals for a record fourth straight time.

The center-back's powerful 13th-minute header decided the nervy encounter between two sides who have traditionally produced sensation matches. 

A female teacher was stabbed to death Friday in front of her pupils at a primary school in the southern French town of Albi by a student's mother, who was immediately detained.

"This morning, a mother showed up with a knife and stabbed a 34-year-old teacher in front of her students, for reasons that will be determined by the investigation," Albi prosecutor Claude Derens told AFP.

France has joined other nations in bolstering security at its airports in line with a U.S. request to enhance screening for direct U.S. flights, aviation officials said Friday.

The new measures "will be carried out in a way to limit as much as possible inconvenience to passengers, however delays are possible," the DGAC civil aviation authority said in a statement.

The traditional Gallic "pot" -- a convivial office drinks party -- may be a thing of the past after the French government on Thursday allowed employers to ban wine from the workplace.

The government had so far exempted wine and cider from the list of alcoholic drinks that employers could ban in offices.

Russian President Vladimir Putin on Thursday expressed "deep concern" over the growing number of civilian casualties and refugees in eastern Ukraine.

"Vladimir Putin expressed deep concern over the growing number of peaceful civilians and a sharp increase in the number of refugees from southeastern Ukraine in Russia," the Kremlin said in a statement after a telephone conversation between Putin, German Chancellor Angela Merkel and French President Francois Hollande.

France's Socialist government on Thursday rejected claims it was using the justice system for political ends after ex-president Nicolas Sarkozy accused his enemies of being behind corruption charges.

Charged with three corruption-related counts on Wednesday, the right-winger angrily hit back in a televised interview, denying he broke the law and denouncing "political interference" in the case.

Nicolas Sarkozy hit back on Wednesday after being charged with corruption, denying he broke the law and suggesting his political enemies were interfering with the French justice system.

"I have never committed any act contrary to the values of the republic or the rule of law," Sarkozy said after he was charged on three corruption-related counts that threaten to torpedo his hopes of a political comeback.

French police early Wednesday cleared a food handout center and three squats in the port of Calais occupied by more than 600 migrants waiting to try to illegally cross the Channel to Britain.

Police cars and dinghies blocked road and sea access to the port after receiving a court order backing local authorities' concerns over sanitary conditions in the food distribution center.

France's former president Nicolas Sarkozy has been charged with corruption and influence peddling, French prosecutors said Wednesday, a dramatic move in a criminal probe that could wreck his hopes of a political comeback. 

The decision came after Sarkozy was questioned for 15 hours, marking the first time a French ex-head of state had been taken into custody in a criminal investigation.

A truck exploded in a huge fireball killing at least 15 people on Tuesday in the northeast Nigerian city of Maiduguri, the latest attack in the area repeatedly hit by Boko Haram Islamists.

The bomb rocked Maiduguri's busiest roundabout near the popular Monday Market during morning rush hour and its force scattered body parts on the rooftops of surrounding shops, according to witnesses.