Amid heightened security ahead of the G20 summit in London on Thursday, five people have been arrested by police.Local media say the suspects are being held under anti-terrorism laws, accused of planning to stage a protest with improvised explosive devices. With some protest groups vowing to cause chaos, many shopkeepers around the venue are nervous. One shopkeeper said: “On Thursday we’ll just try to come in. We’ve got our two IDs with us – passport and driving licence – because police are not letting anyone on the roads. So we’ll try to come in, we’ll see how we go, and if there’s a lot of trouble we’ll shut the shops. But it’s a lot of aggravation because we lose a lot of money.” A local resident said: “I’m just hoping that the meeting they will have will address the world recession, the economic situation around the world especially here in the UK … everyone’s feeling the pinch.” The British Prime Minister says there is a lot of work to be done to strike a deal on tackling the global financial crisis, but he said he was hopeful. World leaders have already started to gather, including the Mexican President, who has attended a reception at Buckingham Palace. President Obama is also due to attend the summit. Debate is expected to focus on restoring global growth and trade and how to improve financial market regulations.