BBC News with Sue Montgomery.

The Olympic torch has arrived in Rio de Janeiro by boat, after three-month tour of Brazilian cities. The Mayor of Rio Eduardo Paes carried the torch on its few laps, but there were chaotic scenes later when the torch relay was challenged by demonstrators. Will Davis is in Rio.

With only two days before the opening ceremony, the Olympic torch is making its way through the industrial district of Brasilia to the north of Rio de Janeiro, when hundreds of protestors angry with the amount of money being spent on the games, try to block its path. With chaotic scenes heavily on, police fired tear gas and pepper spray to demonstrators to try disperse them. This is exactly what Olympic organizers had feared might happen, after all has been a relatively peaceful and sometimes spectacular torch relay around Brazil.

The US Republican presidential candidate Donald Trump has insisted his campaign is united in the face of reports of growing frustration with him amongst the Republican leadership. At a rally in Florida, he said we have never been as united before. But another sign of the levels of exasperation among senior Republican: The former House Speaker, Newt Gingrich, a Trump supporter, said the presidential candidate was helping Hillary Clinton to win by proving he is more unacceptable than she is.

President Obama has commuted the sentences of 214 prison inmates, those who were said to be released include 67 people serving life sentences. Aileen Macbull has more details. Most of the prisoners who have that sentences commuted by the President were convicted of low level drug offences. 214 may seem like lot, and certainly the highest number of inmates to receive a presidential pardon in a single day of America. But the US incarcerates people at a rate far greater than any other major nation. More than two million Americans are behind bars.

Canada has launched an inquiry into the high rates of killings and disappearances of indigenous women and girls, a subject that attracted international criticism. The governments’ indigenous affairs minister Carolyn Bennettcalled the launch historic, stressing the need to examine the roots of the violence. Babara Plat Usher reports. Indigenous women make a four percent of Canada's population, but 16 percent of its homicide victims. More than 1,200 have been murdered or gun missing in the past three decades, and the commission will examine the root causes of this violence. The previous conservative administration blamed it largely on domestic abuse and resistant cause for inquiry, but the current liberal government has linked the high rate of death and disappearances to systemic issues such as racism, sexism and poverty. The commission will also examine policing and child welter policies. The indigenous affairs minister called it an important step in Canada's reconciliation with its native peoples.

World news from the BBC.

Pro-government forces in Lybia say they are making progress in their attack on Islamic State militants’ stronghold of Sirtewith the help of US airstrikes. They say they are advancing house by house in the face of resistance from snipers and bomb attacks.

The Russian military says it’s informed the United States of its belief that rebels in the Syrian city Aleppo use toxic substances in an attack on Tuesday. The Russian news agency ITAR-TASS say seven people died and more than 20 were hospitalized because of the attack. There is no independent confirmation of the claim.

The UN Security Council is holding an emergency session to discuss North Korea's latest ballistic missile test after one of the missiles landed in the waters of Japan's exclusive economic zones. France and Britain said they want strong action taken against North Korea which has carried out a number of tests in the past two weeks in defiance of UN resolutions. Stephane Dujarricis the UN spokesman. We are once again deeply troubled by the latest testifying of missiles by the Democratic Republic of Korea. Such actions seriously undermined regional peace and stability. We reiterate the call on the DPRK to heed the united call of the international community to reverse its course and return to the process of sincere dialogue.

Government scientists in the United States have started clinic trials of vaccine to combat the Zika virus. The first transmissions of the virus by mosquitoes in the US were detected in Florida last week.

The US Supreme Court has blocked to transgender students from using the boys' bathroom at school until an appeal is heard. The order stayed a lower court ruling which had allowed govern groom to use the boys' bathroom at school although he was born a girl. In May, the Obama administration directed schools to allow students to use bathrooms that match the current gender identity.

BBC news.