Picture desk live: the day's best news images

Astonishing scenes as the Waldo Canyon fire burns through an entire neighbourhood near the foothills of Colorado Springs. Colorado has endured nearly a week of near 40C (100F) with low humidity, creating a devastating formula for wildfires Photograph: Helen H Richardson/AP

Bobbie Mesmer, daughter of Gary and Linda Blomenkamp, surveys her parents' house that burned to the ground in the Last Chance Fire in Woodrow, Colorado Photograph: Matthew Jonas/AP

A daring approach by torchbearer Alan Ellinson as he prepares to abseil, one handed, with the Olympic Flame down the side of the Royal Dock Tower in Grimsby at the beginning of Day 40 of the Olympic Torch Relay Photograph: LOCOG/Getty Images

Singer Katy Perry arrives at Katy Perry: Part Of Me Los Angeles Premiere at Grauman's Chinese Theatre in Hollywood wearing a dress that's just made for spinning around in. Who could resist? Photograph: Gregg DeGuire/WireImage

Children lie in the shallows of the Riverwalk at the Mud Island River Park in Memphis, Tennessee, in the heat of the day Photograph: Jim Weber/AP

Andrés Manuel López Obrador, presidential candidate for the Party of the Democratic Revolution (PRD), greets supporters before a rally in Toluca. Mexico will hold presidential elections on Sunday 1 July 2012 Photograph: Edgard Garrido/Reuters

Student protesters have been staging demonstrations calling for electoral transparency in front of Mexico's Televisa network headquarters in Mexico City, after claims that a secretive unit inside Mexico's predominant television network set up and funded a campaign for Enrique Peña Nieto, the leading candidate Photograph: John Moore/Getty Images

You may wonder why, exactly, but zookeepers are taking the footprints of a quokka at Taronga Zoo in Sydney. Staff are collecting the footprints of almost 4,000 animals for a new conservation project in Thailand Photograph: Daniel Munoz/Reuters

Jimmy Vicaut of France is simply a blur as he runs ahead of his competitors during the men's 100 metre heats at the European Athletics Championships in Helsinki Photograph: Dominic Ebenbichler/Reuters

Cambodian police block children from the squatter areas in Boeung Kak during a protest in Phnom Penh. Residents from the squatter areas in Boeung Kak are demanding the release of community members after Phnom Penh City detained residents at a protest on 22 May 2012 Photograph: Mak Remissa/EPA

The convicted residents of the squatter areas in Boeung Kak lakeside raise their handcuffed hands iat the appeal court in Phnom Penh, Cambodia Photograph: Mak Remissa/EPA

The most talked about moment of the Queen's visit to Northern Ireland has almost arrived as the British sovereign prepares to shake hands with Deputy First Minister Martin McGuinness at the Lyric Theatre in Belfast Photograph: Paul Faith/AFP/Getty Images

The Queen shakes the hand of former IRA commander Martin McGuinness, in what is being seen as a hugely significant moment in the Northern Ireland peace process Photograph: Paul Faith/AFP/Getty Images

London's mayor, Boris Johnson, gives a big thumbs up to photographers during the unveiling of the 2012 Olympic rings on Tower Bridge Photograph: Ben Stansall/AFP/Getty Images

Guillaume Olive, project manager of a stunning new exhibition – Light From the Middle East, New Photography at the V&A Museum – holds a photograph by Hassan Hajjaj titled Saida in Green 2000. It looks well worth a visit Photograph: Rosie Hallam/Getty Images

We all know that weary feeling. The German chancellor, Angela Merkel, attends a session of the German Bundestag on the upcoming EU summit in Berlin. Merkel is facing mounting pressure to soften Germany's fierce resistance to jointly issued eurobonds or other forms of debt pooling Photograph: Maja Hitij/AP

Heather Watson's joy is totally contagious as she celebrates her victory on Court Two at Wimbledon today Photograph: Tom Jenkins/Guardian

Whatever the weather Wimbledon always pulls in the crowds Photograph: Dan Kitwood/Getty Images

On the theme of wet Wednesday, spectators narrowly avoid the wash from a boat during the first day of the Henley Royal Regatta Photograph: Steve Parsons/PA

More watery scenes: Gordon McClain, left, surveys his flooded living room in Live Oak, Florida. Dozens of homes and much of the downtown area was flooded by torrential rains from Tropical Storm Debby Photograph: Dave Martin/AP

Bruno Pelizzari, centre, and his partner, Debbie Calitz, left, arrive in Johannesburg. The South African and Italian couple were held hostage for 20 months after being kidnapped in October 2010 from a yacht by Somali pirates. Somali authorities said the couple were rescued in a joint raid by security forces and the army Photograph: Jordi Matas/AFP/Getty Images