With the BBC News.

The head of Russia's Anti-doping Laboratory Grigory Rodchenkov has resigned a day after a report by the World Anti-doping Agency accused Russia of widespread cheating in athletics.Russia's Sports Minister said Mr. Rodchenkov was standing down to take all negativity away with him. Speaking to the BBC, the head of Russia's Athletics Federation Mihayev Gudolf acknowledged there was a problem but it was what he called a mentality problem at coaching level. “We know our problem. We know our problem with doping. And of course we should change mentality of many coaches,especially coaches in the regions. We started in April. We organized some educational programs. We met with a lot of coaches, with a lot of athletes.It's impossible to do immediately, to change immediately. But we started to do it.”

The former head of World Athletics Lamine Diack who's been investigated in France over allegations of corruption and money laundering has been provisionally suspended by the international Olympics Committee. He was an honorary member.

Syrian government forces have ended a 2-year siege by Islamic State militants at the key military airbase in the northern province of Aleppo. An army relief colonel pushed through IS lines and linked up with comrades who have been trapped in the Kuwairis base. State television has shown jubilant soldiers pouring into the area. Analysts say the lifting of the siege constitutes a first significant victory of the government side since Russia stepped in andbegan supporting it with air power.

Prosecutors in the United States have charged two Israelis and one American with what's been described as the largest cyber-attack on financial firms in US history. The men are accused of manipulating share prices, money-laundering and computer-hacking. James Cook reports. “Prosecutors say Gery Shalon who's 31 years old founded and led a sprawling cyber-criminal enterprise with hundreds of employees in more than a dozen countries. His gang is accused of stealing personal information from more than 100 million customers including 83 million of the banking giant JP Morgan Chase. They allegedly use the stolen emails,addresses and telephone numbers to promote companies' stock they had bought cheaply driving up the price before dumping it for vast profits.”

Eight US presidential hopefuls aiming to become the Republican Party's candidates next year are preparing to do battle in Milwaukee shortly in the latest televised presidential debate. Two men from outside the political establishment businessman Donald Trump and retired neurosurgeon Ben Carson are currently leading in the polls. This time the debate is chaired by Fox News. Our correspondent Nick Bryant is in Milwaukee.

“This is Fox News's business channel. They're saying they wanna keep it on the economy. This's a pretty serious naughty question as Jerry Bader is there from the Wall Street Journal impeccable journalist and pedigree kind of for the BBC initially. So we're expecting it a bit more of serious-minded debate tonight.”

World news from the BBC.

The leader of Colombia's largest armed rebel group the FARC has said he had ordered the organization to stop buying new guns and ammunition in September.Rodrigo Londono Echeverri posted a message on Twitter saying the FARC wanted to show its commitment to scaling down the conflict with the Colombia army whichhas begun since the 1960s. The left-wing group and the Colombian governmenthave been engaged in peace talks for nearly three years.

The United Nations says Burundi's political violence is threatening to spiral into a large scale ethnic conflict, similar to that which occurred in neighboring Rwanda in 1994, prompting a genocide in which hundreds of thousands died. But a senior UN human rights official Scott Campbell warned that the UN is today in an even worse position to prevent slaughter. “We actually had United Nations' peace-keeping operation on the ground mandated in Rwanda at the timethe genocide took place. And in Burundi today, we have nothing at all in terms of a political presence or peace-keeping presence.”

Portugal's minority center-right government has been toppled just two weeks after taking power. A coalition of left wing parties voted down the administration's economic program promoting its collapse. This could pave theway for a new anti-austerity government led by the Socialist Party which has promised to increase public spending. Portugal was one of the countries hardest hit by the crisis in the Eurozone accepting an international bailout in exchange for sweeping cuts.

A popular tourist attraction in the United States made up of around a million pieces of bubble gum will soon be a thing of the past. Officials at Pike Place Market in the city of Seattle are blasting the city's famous gum wall with powerful steam cleaners getting rid of a 20 years worth of accumulated goo because they say it attracts rats. People first began sticking there come to the wall while waiting for shows at a nearby theater. It's expected to take three days to clean off the estimated 1000 kilos of gum.

BBC news.